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Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string s[1 ... n] consisting of lowercase Latin letters. It is guaranteed that n = 2^k for some integer k ≥ 0.
The string s[1 ... n] is called c-good if at least one of the following three conditions is satisfied:
* The length of s is 1, and it consists of the character c (i.e. s_1=c);
* The length of s is greater than 1, the first half of the string consists of only the character c (i.e. s_1=s_2=...=s_{n/2}=c) and the second half of the string (i.e. the string s_{n/2 + 1}s_{n/2 + 2} ... s_n) is a (c+1)-good string;
* The length of s is greater than 1, the second half of the string consists of only the character c (i.e. s_{n/2 + 1}=s_{n/2 + 2}=...=s_n=c) and the first half of the string (i.e. the string s_1s_2 ... s_{n/2}) is a (c+1)-good string.
For example: "aabc" is 'a'-good, "ffgheeee" is 'e'-good.
In one move, you can choose one index i from 1 to n and replace s_i with any lowercase Latin letter (any character from 'a' to 'z').
Your task is to find the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string for c= 'a'). It is guaranteed that the answer always exists.
You have to answer t independent test cases.
Another example of an 'a'-good string is as follows. Consider the string s = "cdbbaaaa". It is an 'a'-good string, because:
* the second half of the string ("aaaa") consists of only the character 'a';
* the first half of the string ("cdbb") is 'b'-good string, because:
* the second half of the string ("bb") consists of only the character 'b';
* the first half of the string ("cd") is 'c'-good string, because:
* the first half of the string ("c") consists of only the character 'c';
* the second half of the string ("d") is 'd'-good string.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains one integer n (1 ≤ n ≤ 131~072) — the length of s. It is guaranteed that n = 2^k for some integer k ≥ 0. The second line of the test case contains the string s consisting of n lowercase Latin letters.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string with c = 'a'). It is guaranteed that the answer exists.
Example
Input
6
8
bbdcaaaa
8
asdfghjk
8
ceaaaabb
8
bbaaddcc
1
z
2
ac
Output
0
7
4
5
1
1
|
instruction
| 0
| 98,814
| 0
| 197,628
|
Tags: bitmasks, brute force, divide and conquer, dp, implementation
Correct Solution:
```
from sys import setrecursionlimit,stdout,stdin
setrecursionlimit(100000)
def solve(l, r, c):
if r - l + 1 == 1:
return 1 - (s[l:r + 1] == c)
else:
mid = (r + l + 1) // 2
p1 = 0
p2 = 0
for i in range(l, mid):
p1 += s[i] != c
for i in range(mid, r + 1):
p2 += s[i] != c
ans = min(p1 + solve(mid, r, chr(ord(c) + 1)), solve(l, mid - 1, chr(ord(c) + 1)) + p2)
return ans
for _ in range(int(stdin.readline())):
n = int(stdin.readline())
s = stdin.readline()
print(solve(0, n - 1, 'a'))
```
|
output
| 1
| 98,814
| 0
| 197,629
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string s[1 ... n] consisting of lowercase Latin letters. It is guaranteed that n = 2^k for some integer k ≥ 0.
The string s[1 ... n] is called c-good if at least one of the following three conditions is satisfied:
* The length of s is 1, and it consists of the character c (i.e. s_1=c);
* The length of s is greater than 1, the first half of the string consists of only the character c (i.e. s_1=s_2=...=s_{n/2}=c) and the second half of the string (i.e. the string s_{n/2 + 1}s_{n/2 + 2} ... s_n) is a (c+1)-good string;
* The length of s is greater than 1, the second half of the string consists of only the character c (i.e. s_{n/2 + 1}=s_{n/2 + 2}=...=s_n=c) and the first half of the string (i.e. the string s_1s_2 ... s_{n/2}) is a (c+1)-good string.
For example: "aabc" is 'a'-good, "ffgheeee" is 'e'-good.
In one move, you can choose one index i from 1 to n and replace s_i with any lowercase Latin letter (any character from 'a' to 'z').
Your task is to find the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string for c= 'a'). It is guaranteed that the answer always exists.
You have to answer t independent test cases.
Another example of an 'a'-good string is as follows. Consider the string s = "cdbbaaaa". It is an 'a'-good string, because:
* the second half of the string ("aaaa") consists of only the character 'a';
* the first half of the string ("cdbb") is 'b'-good string, because:
* the second half of the string ("bb") consists of only the character 'b';
* the first half of the string ("cd") is 'c'-good string, because:
* the first half of the string ("c") consists of only the character 'c';
* the second half of the string ("d") is 'd'-good string.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains one integer n (1 ≤ n ≤ 131~072) — the length of s. It is guaranteed that n = 2^k for some integer k ≥ 0. The second line of the test case contains the string s consisting of n lowercase Latin letters.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string with c = 'a'). It is guaranteed that the answer exists.
Example
Input
6
8
bbdcaaaa
8
asdfghjk
8
ceaaaabb
8
bbaaddcc
1
z
2
ac
Output
0
7
4
5
1
1
|
instruction
| 0
| 98,815
| 0
| 197,630
|
Tags: bitmasks, brute force, divide and conquer, dp, implementation
Correct Solution:
```
def get_cnt(start,k,char,s):
result = 0
for index in range(start,start + 2**k):
if s[index] != char:
result += 1
return result
def f(start,k,char,s):
if (k == 0):
if s[start] == char:
return 0
return 1
return min(get_cnt(start,k-1,char,s) + f(start + 2**(k-1),k-1,char + 1,s),f(start,k-1,char + 1,s) + get_cnt(start + 2**(k-1),k-1,char,s))
def solve():
import sys
import math
input = sys.stdin.readline
print = sys.stdout.write
t = int(input())
while t > 0:
n = int(input())
s = [ord(char) - 97 for char in input().strip()]
max_k = int(math.log2(n))
print(f'{f(0,max_k,0,s)}')
print('\n')
t -= 1
solve()
```
|
output
| 1
| 98,815
| 0
| 197,631
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s[1 ... n] consisting of lowercase Latin letters. It is guaranteed that n = 2^k for some integer k ≥ 0.
The string s[1 ... n] is called c-good if at least one of the following three conditions is satisfied:
* The length of s is 1, and it consists of the character c (i.e. s_1=c);
* The length of s is greater than 1, the first half of the string consists of only the character c (i.e. s_1=s_2=...=s_{n/2}=c) and the second half of the string (i.e. the string s_{n/2 + 1}s_{n/2 + 2} ... s_n) is a (c+1)-good string;
* The length of s is greater than 1, the second half of the string consists of only the character c (i.e. s_{n/2 + 1}=s_{n/2 + 2}=...=s_n=c) and the first half of the string (i.e. the string s_1s_2 ... s_{n/2}) is a (c+1)-good string.
For example: "aabc" is 'a'-good, "ffgheeee" is 'e'-good.
In one move, you can choose one index i from 1 to n and replace s_i with any lowercase Latin letter (any character from 'a' to 'z').
Your task is to find the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string for c= 'a'). It is guaranteed that the answer always exists.
You have to answer t independent test cases.
Another example of an 'a'-good string is as follows. Consider the string s = "cdbbaaaa". It is an 'a'-good string, because:
* the second half of the string ("aaaa") consists of only the character 'a';
* the first half of the string ("cdbb") is 'b'-good string, because:
* the second half of the string ("bb") consists of only the character 'b';
* the first half of the string ("cd") is 'c'-good string, because:
* the first half of the string ("c") consists of only the character 'c';
* the second half of the string ("d") is 'd'-good string.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains one integer n (1 ≤ n ≤ 131~072) — the length of s. It is guaranteed that n = 2^k for some integer k ≥ 0. The second line of the test case contains the string s consisting of n lowercase Latin letters.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string with c = 'a'). It is guaranteed that the answer exists.
Example
Input
6
8
bbdcaaaa
8
asdfghjk
8
ceaaaabb
8
bbaaddcc
1
z
2
ac
Output
0
7
4
5
1
1
Submitted Solution:
```
def make_equal(st,n,c):
num=0
for i in range(n):
if(st[i]!=c):
num+=1
return num
def find(st,n,c):
if(n==1):
if(st[0]==c):
return 0
else:
return 1
return min(make_equal(st[0:n//2],n//2,c)+find(st[n//2:],n//2,chr(ord(c)+1)),make_equal(st[n//2:],n//2,c)+find(st[0:n//2],n//2,chr(ord(c)+1)))
t=int(input())
for _ in range(t):
n=int(input())
s=input()
print(find(s,n,'a'))
```
|
instruction
| 0
| 98,816
| 0
| 197,632
|
Yes
|
output
| 1
| 98,816
| 0
| 197,633
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s[1 ... n] consisting of lowercase Latin letters. It is guaranteed that n = 2^k for some integer k ≥ 0.
The string s[1 ... n] is called c-good if at least one of the following three conditions is satisfied:
* The length of s is 1, and it consists of the character c (i.e. s_1=c);
* The length of s is greater than 1, the first half of the string consists of only the character c (i.e. s_1=s_2=...=s_{n/2}=c) and the second half of the string (i.e. the string s_{n/2 + 1}s_{n/2 + 2} ... s_n) is a (c+1)-good string;
* The length of s is greater than 1, the second half of the string consists of only the character c (i.e. s_{n/2 + 1}=s_{n/2 + 2}=...=s_n=c) and the first half of the string (i.e. the string s_1s_2 ... s_{n/2}) is a (c+1)-good string.
For example: "aabc" is 'a'-good, "ffgheeee" is 'e'-good.
In one move, you can choose one index i from 1 to n and replace s_i with any lowercase Latin letter (any character from 'a' to 'z').
Your task is to find the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string for c= 'a'). It is guaranteed that the answer always exists.
You have to answer t independent test cases.
Another example of an 'a'-good string is as follows. Consider the string s = "cdbbaaaa". It is an 'a'-good string, because:
* the second half of the string ("aaaa") consists of only the character 'a';
* the first half of the string ("cdbb") is 'b'-good string, because:
* the second half of the string ("bb") consists of only the character 'b';
* the first half of the string ("cd") is 'c'-good string, because:
* the first half of the string ("c") consists of only the character 'c';
* the second half of the string ("d") is 'd'-good string.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains one integer n (1 ≤ n ≤ 131~072) — the length of s. It is guaranteed that n = 2^k for some integer k ≥ 0. The second line of the test case contains the string s consisting of n lowercase Latin letters.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string with c = 'a'). It is guaranteed that the answer exists.
Example
Input
6
8
bbdcaaaa
8
asdfghjk
8
ceaaaabb
8
bbaaddcc
1
z
2
ac
Output
0
7
4
5
1
1
Submitted Solution:
```
import math
from decimal import *
import random
import sys
sys.setrecursionlimit(10**6)
mod = int(1e9)+7
def dfs(arr, ans, c):
if(len(arr)==1):
if(arr[0]!=c):
ans+=1
return ans
if(len(arr)==0):
return ans
else:
tmpl, tmpr = int(ans),int(ans)
for i in range(len(arr)//2):
if(arr[i]!= c):
tmpl+=1
if(arr[len(arr)//2+i]!= c):
tmpr+=1
ans = min(dfs(arr[:len(arr)//2], tmpr, chr(ord(c)+1)),
dfs(arr[len(arr)//2:], tmpl, chr(ord(c)+1)))
return ans
for _ in range(int(input())):
n = int(input())
s = list(input())
ans = dfs(s, 0, 'a')
print(ans)
```
|
instruction
| 0
| 98,817
| 0
| 197,634
|
Yes
|
output
| 1
| 98,817
| 0
| 197,635
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s[1 ... n] consisting of lowercase Latin letters. It is guaranteed that n = 2^k for some integer k ≥ 0.
The string s[1 ... n] is called c-good if at least one of the following three conditions is satisfied:
* The length of s is 1, and it consists of the character c (i.e. s_1=c);
* The length of s is greater than 1, the first half of the string consists of only the character c (i.e. s_1=s_2=...=s_{n/2}=c) and the second half of the string (i.e. the string s_{n/2 + 1}s_{n/2 + 2} ... s_n) is a (c+1)-good string;
* The length of s is greater than 1, the second half of the string consists of only the character c (i.e. s_{n/2 + 1}=s_{n/2 + 2}=...=s_n=c) and the first half of the string (i.e. the string s_1s_2 ... s_{n/2}) is a (c+1)-good string.
For example: "aabc" is 'a'-good, "ffgheeee" is 'e'-good.
In one move, you can choose one index i from 1 to n and replace s_i with any lowercase Latin letter (any character from 'a' to 'z').
Your task is to find the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string for c= 'a'). It is guaranteed that the answer always exists.
You have to answer t independent test cases.
Another example of an 'a'-good string is as follows. Consider the string s = "cdbbaaaa". It is an 'a'-good string, because:
* the second half of the string ("aaaa") consists of only the character 'a';
* the first half of the string ("cdbb") is 'b'-good string, because:
* the second half of the string ("bb") consists of only the character 'b';
* the first half of the string ("cd") is 'c'-good string, because:
* the first half of the string ("c") consists of only the character 'c';
* the second half of the string ("d") is 'd'-good string.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains one integer n (1 ≤ n ≤ 131~072) — the length of s. It is guaranteed that n = 2^k for some integer k ≥ 0. The second line of the test case contains the string s consisting of n lowercase Latin letters.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string with c = 'a'). It is guaranteed that the answer exists.
Example
Input
6
8
bbdcaaaa
8
asdfghjk
8
ceaaaabb
8
bbaaddcc
1
z
2
ac
Output
0
7
4
5
1
1
Submitted Solution:
```
from collections import Counter
def cal(l, r, i):
if l == r:
if s[l] == i:
return 0
else:
return 1
m = (l+r)//2
cnt1 = Counter(s[l:m+1])
cnt2 = Counter(s[m+1:r+1])
l1 = (r-l+1)//2 - cnt1.get(i, 0) + cal(m+1, r, i+1)
l2 = (r-l+1)//2 - cnt2.get(i, 0) + cal(l, m, i+1)
return min(l1, l2)
x = int(input())
for i in range(x):
n = int(input())
s = input()
s = [ord(i)-ord('a') for i in s]
print(cal(0, len(s)-1, 0))
```
|
instruction
| 0
| 98,818
| 0
| 197,636
|
Yes
|
output
| 1
| 98,818
| 0
| 197,637
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s[1 ... n] consisting of lowercase Latin letters. It is guaranteed that n = 2^k for some integer k ≥ 0.
The string s[1 ... n] is called c-good if at least one of the following three conditions is satisfied:
* The length of s is 1, and it consists of the character c (i.e. s_1=c);
* The length of s is greater than 1, the first half of the string consists of only the character c (i.e. s_1=s_2=...=s_{n/2}=c) and the second half of the string (i.e. the string s_{n/2 + 1}s_{n/2 + 2} ... s_n) is a (c+1)-good string;
* The length of s is greater than 1, the second half of the string consists of only the character c (i.e. s_{n/2 + 1}=s_{n/2 + 2}=...=s_n=c) and the first half of the string (i.e. the string s_1s_2 ... s_{n/2}) is a (c+1)-good string.
For example: "aabc" is 'a'-good, "ffgheeee" is 'e'-good.
In one move, you can choose one index i from 1 to n and replace s_i with any lowercase Latin letter (any character from 'a' to 'z').
Your task is to find the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string for c= 'a'). It is guaranteed that the answer always exists.
You have to answer t independent test cases.
Another example of an 'a'-good string is as follows. Consider the string s = "cdbbaaaa". It is an 'a'-good string, because:
* the second half of the string ("aaaa") consists of only the character 'a';
* the first half of the string ("cdbb") is 'b'-good string, because:
* the second half of the string ("bb") consists of only the character 'b';
* the first half of the string ("cd") is 'c'-good string, because:
* the first half of the string ("c") consists of only the character 'c';
* the second half of the string ("d") is 'd'-good string.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains one integer n (1 ≤ n ≤ 131~072) — the length of s. It is guaranteed that n = 2^k for some integer k ≥ 0. The second line of the test case contains the string s consisting of n lowercase Latin letters.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string with c = 'a'). It is guaranteed that the answer exists.
Example
Input
6
8
bbdcaaaa
8
asdfghjk
8
ceaaaabb
8
bbaaddcc
1
z
2
ac
Output
0
7
4
5
1
1
Submitted Solution:
```
def cnt(s, c):
x = 0
for i in s:
if i != c:
x += 1
return x
def search(s, n, cho):
c = chr(cho)
if n == 1:
return 0 if s[0] == c else 1
m = n // 2
s1 = s[:m]
s2 = s[m:]
x = cnt(s1, c) + search(s2, m, cho+1)
y = search(s1, m, cho+1) + cnt(s2, c)
return min(x, y)
t = int(input())
for _ in range(t):
n = int(input())
s = input()
#print(s)
l = 0
r = n
moves = 0
cho = ord('a')
print(search(s, n, cho))
continue
while r - l > 1:
ch = chr(cho)
m = (l + r) // 2
x = cnt(s, l, m, ch)
y = cnt(s, m, r, ch)
lng = m - l
print(f"ch={ch}, l={l}, m={m}, r={r}, x={x}, y={y}")
if x > y:
moves += lng - x
l = m
else:
moves += lng - y
r = m
cho += 1
print(f"l={l}, moves={moves}, ch=>{chr(cho)}")
else:
if s[l] != chr(cho):
moves += 1
print(moves)
```
|
instruction
| 0
| 98,819
| 0
| 197,638
|
Yes
|
output
| 1
| 98,819
| 0
| 197,639
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s[1 ... n] consisting of lowercase Latin letters. It is guaranteed that n = 2^k for some integer k ≥ 0.
The string s[1 ... n] is called c-good if at least one of the following three conditions is satisfied:
* The length of s is 1, and it consists of the character c (i.e. s_1=c);
* The length of s is greater than 1, the first half of the string consists of only the character c (i.e. s_1=s_2=...=s_{n/2}=c) and the second half of the string (i.e. the string s_{n/2 + 1}s_{n/2 + 2} ... s_n) is a (c+1)-good string;
* The length of s is greater than 1, the second half of the string consists of only the character c (i.e. s_{n/2 + 1}=s_{n/2 + 2}=...=s_n=c) and the first half of the string (i.e. the string s_1s_2 ... s_{n/2}) is a (c+1)-good string.
For example: "aabc" is 'a'-good, "ffgheeee" is 'e'-good.
In one move, you can choose one index i from 1 to n and replace s_i with any lowercase Latin letter (any character from 'a' to 'z').
Your task is to find the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string for c= 'a'). It is guaranteed that the answer always exists.
You have to answer t independent test cases.
Another example of an 'a'-good string is as follows. Consider the string s = "cdbbaaaa". It is an 'a'-good string, because:
* the second half of the string ("aaaa") consists of only the character 'a';
* the first half of the string ("cdbb") is 'b'-good string, because:
* the second half of the string ("bb") consists of only the character 'b';
* the first half of the string ("cd") is 'c'-good string, because:
* the first half of the string ("c") consists of only the character 'c';
* the second half of the string ("d") is 'd'-good string.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains one integer n (1 ≤ n ≤ 131~072) — the length of s. It is guaranteed that n = 2^k for some integer k ≥ 0. The second line of the test case contains the string s consisting of n lowercase Latin letters.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string with c = 'a'). It is guaranteed that the answer exists.
Example
Input
6
8
bbdcaaaa
8
asdfghjk
8
ceaaaabb
8
bbaaddcc
1
z
2
ac
Output
0
7
4
5
1
1
Submitted Solution:
```
count=0
def c(li,l,h,good):
global count
if(h-l==1):
if(li[l]==good):
return 0
return 1
m=l+(h-l)//2
if(li[l:m].count(good)>li[m:h].count(good)):
return (h-l)//2-li[l:m].count(good) +c(li,m,h,chr(ord(good)+1))
elif(li[l:m].count(good)<li[m:h].count(good)):
return (h-l)//2-li[m:h].count(good) +c(li,l,m,chr(ord(good)+1))
else:
if(li[l:m].count(chr(ord(good)+1))>li[m:h].count(chr(ord(good)+1))):
return (h-l)//2-li[m:h].count(good) +c(li,l,m,chr(ord(good)+1))
else:
return (h-l)//2-li[l:m].count(good) +c(li,m,h,chr(ord(good)+1))
def main():
for _ in range(int(input())):
n=int(input())
a=list(input())
print(c(a,0,n,'a'))
main()
```
|
instruction
| 0
| 98,820
| 0
| 197,640
|
No
|
output
| 1
| 98,820
| 0
| 197,641
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s[1 ... n] consisting of lowercase Latin letters. It is guaranteed that n = 2^k for some integer k ≥ 0.
The string s[1 ... n] is called c-good if at least one of the following three conditions is satisfied:
* The length of s is 1, and it consists of the character c (i.e. s_1=c);
* The length of s is greater than 1, the first half of the string consists of only the character c (i.e. s_1=s_2=...=s_{n/2}=c) and the second half of the string (i.e. the string s_{n/2 + 1}s_{n/2 + 2} ... s_n) is a (c+1)-good string;
* The length of s is greater than 1, the second half of the string consists of only the character c (i.e. s_{n/2 + 1}=s_{n/2 + 2}=...=s_n=c) and the first half of the string (i.e. the string s_1s_2 ... s_{n/2}) is a (c+1)-good string.
For example: "aabc" is 'a'-good, "ffgheeee" is 'e'-good.
In one move, you can choose one index i from 1 to n and replace s_i with any lowercase Latin letter (any character from 'a' to 'z').
Your task is to find the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string for c= 'a'). It is guaranteed that the answer always exists.
You have to answer t independent test cases.
Another example of an 'a'-good string is as follows. Consider the string s = "cdbbaaaa". It is an 'a'-good string, because:
* the second half of the string ("aaaa") consists of only the character 'a';
* the first half of the string ("cdbb") is 'b'-good string, because:
* the second half of the string ("bb") consists of only the character 'b';
* the first half of the string ("cd") is 'c'-good string, because:
* the first half of the string ("c") consists of only the character 'c';
* the second half of the string ("d") is 'd'-good string.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains one integer n (1 ≤ n ≤ 131~072) — the length of s. It is guaranteed that n = 2^k for some integer k ≥ 0. The second line of the test case contains the string s consisting of n lowercase Latin letters.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string with c = 'a'). It is guaranteed that the answer exists.
Example
Input
6
8
bbdcaaaa
8
asdfghjk
8
ceaaaabb
8
bbaaddcc
1
z
2
ac
Output
0
7
4
5
1
1
Submitted Solution:
```
from sys import stdin, stdout, setrecursionlimit
from collections import deque, defaultdict, Counter
from functools import lru_cache
from heapq import heappush, heappop
import math
setrecursionlimit(100000)
rl = lambda: stdin.readline()
rll = lambda: stdin.readline().split()
rli = lambda: map(int, stdin.readline().split())
rlf = lambda: map(float, stdin.readline().split())
INF, NINF = float('inf'), float('-inf')
tonum = lambda c: ord(c) - 97
tochr = lambda num: chr(num + 97)
def solv(s, i, j, need):
if i > j: return 0
if i == j: return 0 if s[i] == tochr(need) else 1
mid = (i + j)//2
cnt1, cnt2 = 0, 0
cneed = tochr(need)
for x in range(i, mid+1):
if s[x] != cneed: cnt1 += 1
for x in range(mid+1, j+1):
if s[x] != cneed: cnt2 += 1
# print(f"i, j, need, mid = {i, j, cneed, mid}. fix_a = {cnt1}, fix_b = {cnt2}")
if cnt1 < cnt2:
return cnt1 + solv(s, mid+1, j, need+1)
elif cnt2 > cnt1:
return cnt2 + solv(s, i, mid, need+1)
else:
return min(cnt1+solv(s,mid+1,j,need+1), cnt2+solv(s,i,mid,need+1))
def main():
T = int(rl())
for _ in range(T):
n = int(rl())
s = rll()[0]
x = solv(s, 0, len(s)-1, 0)
print(x)
stdout.close()
if __name__ == "__main__":
main()
```
|
instruction
| 0
| 98,821
| 0
| 197,642
|
No
|
output
| 1
| 98,821
| 0
| 197,643
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s[1 ... n] consisting of lowercase Latin letters. It is guaranteed that n = 2^k for some integer k ≥ 0.
The string s[1 ... n] is called c-good if at least one of the following three conditions is satisfied:
* The length of s is 1, and it consists of the character c (i.e. s_1=c);
* The length of s is greater than 1, the first half of the string consists of only the character c (i.e. s_1=s_2=...=s_{n/2}=c) and the second half of the string (i.e. the string s_{n/2 + 1}s_{n/2 + 2} ... s_n) is a (c+1)-good string;
* The length of s is greater than 1, the second half of the string consists of only the character c (i.e. s_{n/2 + 1}=s_{n/2 + 2}=...=s_n=c) and the first half of the string (i.e. the string s_1s_2 ... s_{n/2}) is a (c+1)-good string.
For example: "aabc" is 'a'-good, "ffgheeee" is 'e'-good.
In one move, you can choose one index i from 1 to n and replace s_i with any lowercase Latin letter (any character from 'a' to 'z').
Your task is to find the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string for c= 'a'). It is guaranteed that the answer always exists.
You have to answer t independent test cases.
Another example of an 'a'-good string is as follows. Consider the string s = "cdbbaaaa". It is an 'a'-good string, because:
* the second half of the string ("aaaa") consists of only the character 'a';
* the first half of the string ("cdbb") is 'b'-good string, because:
* the second half of the string ("bb") consists of only the character 'b';
* the first half of the string ("cd") is 'c'-good string, because:
* the first half of the string ("c") consists of only the character 'c';
* the second half of the string ("d") is 'd'-good string.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains one integer n (1 ≤ n ≤ 131~072) — the length of s. It is guaranteed that n = 2^k for some integer k ≥ 0. The second line of the test case contains the string s consisting of n lowercase Latin letters.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string with c = 'a'). It is guaranteed that the answer exists.
Example
Input
6
8
bbdcaaaa
8
asdfghjk
8
ceaaaabb
8
bbaaddcc
1
z
2
ac
Output
0
7
4
5
1
1
Submitted Solution:
```
from sys import stdin
input = lambda: stdin.readline().rstrip("\r\n")
from collections import deque as que, defaultdict as vector
from heapq import*
inin = lambda: int(input())
inar = lambda: list(map(int,input().split()))
from math import log2
def solve(c,st):
cnt=0
for i in st:
if i!=c:
cnt+=1
return cnt
alp='abcdefghijklmnopqrstuvwxyz'
Testcase=inin()
for i in range(Testcase):
n=inin()
s=input()
sc=s
k=int(log2(n)+1)
copy=k
#print(k)
ans=0
while(k):
c=alp[copy-k]
k-=1
#print(c)
n=len(s)
if len(s)==1:
ans+= solve(c,s)
break
l=solve(c,s[0:2**(k-1)])
r=solve(c,s[2**(k-1):n])
#print(s[0:2**(k-1)],s[2**(k-1):n])
#print(l,r)
if l<r:
s=s[2**(k-1):n]
ans+=l
else:
s=s[0:2**(k-1)]
#print(s[0:2**(k-1)])
ans+=r
ans1=0
k=copy
s=sc
while(k):
c=alp[copy-k]
k-=1
#print(c)
n=len(s)
if len(s)==1:
ans1+= solve(c,s)
break
l=solve(c,s[0:2**(k-1)])
r=solve(c,s[2**(k-1):n])
#print(s[0:2**(k-1)],s[2**(k-1):n])
#print(l,r)
if l<=r:
s=s[2**(k-1):n]
ans1+=l
else:
s=s[0:2**(k-1)]
#print(s[0:2**(k-1)])
ans1+=r
print(min(ans,ans1))
```
|
instruction
| 0
| 98,822
| 0
| 197,644
|
No
|
output
| 1
| 98,822
| 0
| 197,645
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s[1 ... n] consisting of lowercase Latin letters. It is guaranteed that n = 2^k for some integer k ≥ 0.
The string s[1 ... n] is called c-good if at least one of the following three conditions is satisfied:
* The length of s is 1, and it consists of the character c (i.e. s_1=c);
* The length of s is greater than 1, the first half of the string consists of only the character c (i.e. s_1=s_2=...=s_{n/2}=c) and the second half of the string (i.e. the string s_{n/2 + 1}s_{n/2 + 2} ... s_n) is a (c+1)-good string;
* The length of s is greater than 1, the second half of the string consists of only the character c (i.e. s_{n/2 + 1}=s_{n/2 + 2}=...=s_n=c) and the first half of the string (i.e. the string s_1s_2 ... s_{n/2}) is a (c+1)-good string.
For example: "aabc" is 'a'-good, "ffgheeee" is 'e'-good.
In one move, you can choose one index i from 1 to n and replace s_i with any lowercase Latin letter (any character from 'a' to 'z').
Your task is to find the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string for c= 'a'). It is guaranteed that the answer always exists.
You have to answer t independent test cases.
Another example of an 'a'-good string is as follows. Consider the string s = "cdbbaaaa". It is an 'a'-good string, because:
* the second half of the string ("aaaa") consists of only the character 'a';
* the first half of the string ("cdbb") is 'b'-good string, because:
* the second half of the string ("bb") consists of only the character 'b';
* the first half of the string ("cd") is 'c'-good string, because:
* the first half of the string ("c") consists of only the character 'c';
* the second half of the string ("d") is 'd'-good string.
Input
The first line of the input contains one integer t (1 ≤ t ≤ 2 ⋅ 10^4) — the number of test cases. Then t test cases follow.
The first line of the test case contains one integer n (1 ≤ n ≤ 131~072) — the length of s. It is guaranteed that n = 2^k for some integer k ≥ 0. The second line of the test case contains the string s consisting of n lowercase Latin letters.
It is guaranteed that the sum of n does not exceed 2 ⋅ 10^5 (∑ n ≤ 2 ⋅ 10^5).
Output
For each test case, print the answer — the minimum number of moves required to obtain an 'a'-good string from s (i.e. c-good string with c = 'a'). It is guaranteed that the answer exists.
Example
Input
6
8
bbdcaaaa
8
asdfghjk
8
ceaaaabb
8
bbaaddcc
1
z
2
ac
Output
0
7
4
5
1
1
Submitted Solution:
```
def rec(s,c):
n=len(s)
if n==2:
if s[0]==c and s[1]==chr(ord(c)+1):
return 0
elif s[1]==c and s[0]==chr(ord(c)+1):
return 0
elif s[0]==c:
return 1
elif s[1]==c:
return 1
else:
return 2
a1,a2=0,0
for i in range(n//2):
if s[i]!=c:
a1+=1
for i in range(n//2,n):
if s[i]!=c:
a2+=1
an1=rec(s[n//2:],chr(ord(c)+1))+a1
an2=rec(s[:n//2],chr(ord(c)+1))+a2
return min(an1,an2)
t=int(input())
for q in range(t):
n=int(input())
s=input()
if n==1:
if s[0]=='a':
print(0)
else:
print(1)
else:
print(rec(s,'a'))
```
|
instruction
| 0
| 98,823
| 0
| 197,646
|
No
|
output
| 1
| 98,823
| 0
| 197,647
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
|
instruction
| 0
| 99,207
| 0
| 198,414
|
Tags: implementation, strings
Correct Solution:
```
if __name__ == '__main__':
n = int(input())
ss = input()
ans = n
for i in range(1, n // 2+1):
if ss[0: i] == ss[i:i+i]:
ans = n - i + 1
print(ans)
```
|
output
| 1
| 99,207
| 0
| 198,415
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
|
instruction
| 0
| 99,208
| 0
| 198,416
|
Tags: implementation, strings
Correct Solution:
```
n = int(input())
s = input()
size = 0
i = n-1
while i>-1:
if i%2 ==0:
size+=1
i-=1
elif s[:(i+1)//2]==s[(i+1)//2:(i+1)]:
size +=(i+1)//2+1
break
else:
size +=2
i-=2
print(size)
```
|
output
| 1
| 99,208
| 0
| 198,417
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
|
instruction
| 0
| 99,209
| 0
| 198,418
|
Tags: implementation, strings
Correct Solution:
```
n = int(input())
s = input()
m = ''
for i in range(1, len(s)):
if s[0:i] == s[i:i * 2] and len(s[0:i]) > len(m):
m = s[0:i]
if len(m) == 0:
print(len(s))
else:
print(len(s) - len(m) + 1)
```
|
output
| 1
| 99,209
| 0
| 198,419
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
|
instruction
| 0
| 99,210
| 0
| 198,420
|
Tags: implementation, strings
Correct Solution:
```
import getpass
import sys
import math
import random
import itertools
import bisect
import time
files = True
debug = False
if getpass.getuser() == 'frohenk' and files:
debug = True
sys.stdin = open("test.in")
# sys.stdout = open('test.out', 'w')
elif files:
# fname = "gift"
# sys.stdin = open("%s.in" % fname)
# sys.stdout = open('%s.out' % fname, 'w')
pass
def lcm(a, b):
return a * b // math.gcd(a, b)
def ria():
return [int(i) for i in input().split()]
def range_sum(a, b):
ass = (((b - a + 1) // 2) * (a + b))
if (a - b) % 2 == 0:
ass += (b - a + 2) // 2
return ass
def comba(n, x):
return (math.factorial(n) // math.factorial(n - x)) // math.factorial(x)
n = ria()[0]
suma = n
st = input()
mx = 0
for i in range(1, n + 1):
if i + i <= n:
if st[:i] == st[i:i + i]:
mx = max(mx, len(st[:i]) - 1)
print(n - mx)
```
|
output
| 1
| 99,210
| 0
| 198,421
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
|
instruction
| 0
| 99,211
| 0
| 198,422
|
Tags: implementation, strings
Correct Solution:
```
n=int(input())
st = input()
c=0
x=0
ok = 0
for i in range(1,n//2+1):
# print(st[:x+1],st[x+1:2*x+2])
if st[ : i]==st[i:2*i]:
x=i
print(min([n,n-x+1]))
```
|
output
| 1
| 99,211
| 0
| 198,423
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
|
instruction
| 0
| 99,212
| 0
| 198,424
|
Tags: implementation, strings
Correct Solution:
```
L = int(input())
s = input()
for i in range(L//2, 2-1, -1):
if s[i:].startswith(s[:i]):
print(L-i+1)
break
else:
print(L)
```
|
output
| 1
| 99,212
| 0
| 198,425
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
|
instruction
| 0
| 99,213
| 0
| 198,426
|
Tags: implementation, strings
Correct Solution:
```
n = int(input())
s = input()
for l in range(n // 2, 0, -1):
if s[:l] == s[l:l * 2]:
print(len(s) - l + 1)
exit(0)
print(n)
```
|
output
| 1
| 99,213
| 0
| 198,427
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
|
instruction
| 0
| 99,214
| 0
| 198,428
|
Tags: implementation, strings
Correct Solution:
```
#codeforces_954B
n = int(input())
k = n
s = input()
rez = 0
while n>0:
if n & 1:
n -= 1
pass;
elif s[:n//2] == s[n//2:n]:
rez = n//2 +1
break;
else:
n -= 2
print(k-n+rez)
```
|
output
| 1
| 99,214
| 0
| 198,429
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
Submitted Solution:
```
n = int(input())
s = input()
ans = n
for i in range(n):
if 2 * i <= n and s[:i] == s[i: 2 * i]:
ans = min(ans, n - i + 1)
print(ans)
```
|
instruction
| 0
| 99,215
| 0
| 198,430
|
Yes
|
output
| 1
| 99,215
| 0
| 198,431
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
Submitted Solution:
```
n=int(input()); ans=0; u=n*[0]
s=input()
for t in range(n):
if t%2==1:
if s[:int((t+1)/2)]==s[int((t+1)/2):(t+1)]:
ans=t
print (int((ans+1)/2)+1+n-ans-1)
```
|
instruction
| 0
| 99,216
| 0
| 198,432
|
Yes
|
output
| 1
| 99,216
| 0
| 198,433
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
Submitted Solution:
```
n = int(input())
s = str(input())
ans = len(s)
for i in range(1, n+1):
if s[:i] + s[:i] == s[:2*i] and 2*i <= n:
ans = min(ans, n-i+1)
print(ans)
```
|
instruction
| 0
| 99,217
| 0
| 198,434
|
Yes
|
output
| 1
| 99,217
| 0
| 198,435
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
Submitted Solution:
```
n = int(input())
str1 = input()
x = 0
for i in range(1, n//2 +1):
if str1[:i] == str1[i:i*2]:
x=i
print( n - max(x-1 , 0))
```
|
instruction
| 0
| 99,218
| 0
| 198,436
|
Yes
|
output
| 1
| 99,218
| 0
| 198,437
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
Submitted Solution:
```
z=input()
x=input()
l=int(z)
n=0
while(n<=l/2):
if x[0:n]==x[n+1:2*n+1]:
great=n
n=n+1
print(l-great)
```
|
instruction
| 0
| 99,219
| 0
| 198,438
|
No
|
output
| 1
| 99,219
| 0
| 198,439
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
Submitted Solution:
```
n = int(input())
s = input()
for k in range(n // 2, 0, -1):
for i in range(n):
if i + k + k > n:
break
if s[i:i + k] == s[i + k: i + k + k]:
print(n - k + 1)
exit(0)
print(n)
```
|
instruction
| 0
| 99,220
| 0
| 198,440
|
No
|
output
| 1
| 99,220
| 0
| 198,441
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
Submitted Solution:
```
x = int(input())
y = input()
def operations(x):
if x == 0:
return 0
if x % 2 == 0:
part = int(x/2)
if y[0:part] == y[part:2*part]:
return part
else:
return 1 + operations(x-1)
else:
return 1 + operations(x-1)
```
|
instruction
| 0
| 99,221
| 0
| 198,442
|
No
|
output
| 1
| 99,221
| 0
| 198,443
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string s consisting of n lowercase Latin letters. You have to type this string using your keyboard.
Initially, you have an empty string. Until you type the whole string, you may perform the following operation:
* add a character to the end of the string.
Besides, at most once you may perform one additional operation: copy the string and append it to itself.
For example, if you have to type string abcabca, you can type it in 7 operations if you type all the characters one by one. However, you can type it in 5 operations if you type the string abc first and then copy it and type the last character.
If you have to type string aaaaaaaaa, the best option is to type 4 characters one by one, then copy the string, and then type the remaining character.
Print the minimum number of operations you need to type the given string.
Input
The first line of the input containing only one integer number n (1 ≤ n ≤ 100) — the length of the string you have to type. The second line containing the string s consisting of n lowercase Latin letters.
Output
Print one integer number — the minimum number of operations you need to type the given string.
Examples
Input
7
abcabca
Output
5
Input
8
abcdefgh
Output
8
Note
The first test described in the problem statement.
In the second test you can only type all the characters one by one.
Submitted Solution:
```
a= input()
ho=0
for i in range(0, len(a)//2):
if(a[0:i] == a[i:2*i]):
ho=i
ho=ho+1
an=len(a)-ho
print(an)
```
|
instruction
| 0
| 99,222
| 0
| 198,444
|
No
|
output
| 1
| 99,222
| 0
| 198,445
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
|
instruction
| 0
| 99,476
| 0
| 198,952
|
Tags: implementation, strings
Correct Solution:
```
# Author: S Mahesh Raju
# Username: maheshraju2020
# Date: 18/07/2020
from sys import stdin,stdout
from math import gcd, ceil, sqrt
from collections import Counter
from bisect import bisect_left, bisect_right
ii1 = lambda: int(stdin.readline().strip())
is1 = lambda: stdin.readline().strip()
iia = lambda: list(map(int, stdin.readline().strip().split()))
isa = lambda: stdin.readline().strip().split()
mod = 1000000007
def lps(s):
arr = [0] * (len(s))
i, j = 1, 0
while i < len(s):
if s[i] == s[j]:
arr[i] = j + 1
j += 1
else:
while j > 0 and s[i] != s[j]:
j = arr[j - 1]
if s[i] == s[j]:
arr[i] = j + 1
j += 1
i += 1
return arr
n, k = iia()
t = is1()
common = lps(t)[-1]
res = t
for i in range(k - 1):
res += t[common:]
print(res)
```
|
output
| 1
| 99,476
| 0
| 198,953
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
|
instruction
| 0
| 99,477
| 0
| 198,954
|
Tags: implementation, strings
Correct Solution:
```
n,k=map(int,input().split())
t=input()
idx=0
for i in range(1,n):
if t[:n-i]==t[i:]:
idx=i
break
ans=t
appendix=""
if idx==0:
appendix=t
else:
appendix=t[n-idx:]
for i in range(k-1):
ans+=appendix
print(ans)
```
|
output
| 1
| 99,477
| 0
| 198,955
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
|
instruction
| 0
| 99,478
| 0
| 198,956
|
Tags: implementation, strings
Correct Solution:
```
n, k = map(int, input().split())
t = input()
merge_index = None
for i in range(1, n):
if t[i:] == t[:-i]:
merge_index = i
break
if merge_index is not None:
res = []
for i in range(k):
res.append(t[:merge_index])
res.append(t[merge_index:])
else:
res = [t] * k
print(''.join(res))
```
|
output
| 1
| 99,478
| 0
| 198,957
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
|
instruction
| 0
| 99,479
| 0
| 198,958
|
Tags: implementation, strings
Correct Solution:
```
from collections import *
n,k = map(int,input().split())
s = input()
ind = n
for i in range(1,n):
if(s[:n-i] == s[i:]):
ind = i
break
t = s+(s[n-ind:])*(k-1)
print(t)
```
|
output
| 1
| 99,479
| 0
| 198,959
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
|
instruction
| 0
| 99,480
| 0
| 198,960
|
Tags: implementation, strings
Correct Solution:
```
n, k = (int(x) for x in input().split())
t = input()
t1 = ""
for i in range(1,n+1):
if t[:n-i] == t[i:]:
t1 += t[:i]*k
t1 += t[i:]
print(t1)
break
```
|
output
| 1
| 99,480
| 0
| 198,961
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
|
instruction
| 0
| 99,481
| 0
| 198,962
|
Tags: implementation, strings
Correct Solution:
```
n,k=map(int,input().split())
string=input()
counter=0
for i in range(1,len(string)):
if string[:i]==string[-i:]:
counter=i
print(string+string[counter:]*(k-1))
```
|
output
| 1
| 99,481
| 0
| 198,963
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
|
instruction
| 0
| 99,482
| 0
| 198,964
|
Tags: implementation, strings
Correct Solution:
```
k=int(input().split()[1])
t=input()
i=1
while t[i:]!=t[:-i]:i+=1
print(t[:i]*k+t[i:])
```
|
output
| 1
| 99,482
| 0
| 198,965
|
Provide tags and a correct Python 3 solution for this coding contest problem.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
|
instruction
| 0
| 99,483
| 0
| 198,966
|
Tags: implementation, strings
Correct Solution:
```
n, k = map(int, input().split())
t = input()
P = [0] * n
for i in range(1, n):
j = P[i - 1]
while t[j] != t[i] and j > 0:
j = P[j - 1]
if t[i] == t[j]:
j += 1
P[i] = j
ans = t[:(n - P[n - 1])] * k
if P[n - 1] > 0:
ans += t[(n - P[n - 1]):]
print(ans)
```
|
output
| 1
| 99,483
| 0
| 198,967
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
Submitted Solution:
```
n,k = input().split(' ')
mot = input()
n = int(n)
k = int(k)
max = 0
for i in range(1,n):
if mot[:i] == mot[-i:]:
max = i
s = mot
print(mot + (k-1)*mot[max:])
```
|
instruction
| 0
| 99,484
| 0
| 198,968
|
Yes
|
output
| 1
| 99,484
| 0
| 198,969
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
Submitted Solution:
```
# -*- coding: utf-8 -*-
from sys import stdin, stdout
n, k = [int(x) for x in stdin.readline().rstrip().split()]
t = stdin.readline()
for i in range(n):
if t[0:i] == t[n-i:n]:
s = t[0:n-i]
print(s*(k-1) + t)
```
|
instruction
| 0
| 99,485
| 0
| 198,970
|
Yes
|
output
| 1
| 99,485
| 0
| 198,971
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
Submitted Solution:
```
n, k = map(int, input().split())
s = input()
for i in range(1, n + 1):
if s in s[i:] + s[-i:]:
ans = i
break
print(s, end='')
for i in range(k - 1):
print(s[-ans:], end ='')
```
|
instruction
| 0
| 99,486
| 0
| 198,972
|
Yes
|
output
| 1
| 99,486
| 0
| 198,973
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
Submitted Solution:
```
##
n,k=map(int,input().split())
s=input()
ind=0
r2=s[::]
for i in range(0,n-1):
if s[0:i+1]==s[n-i-1:]:
r2=s[i+1:]
ans=s+r2*(k-1)
print(ans)
```
|
instruction
| 0
| 99,487
| 0
| 198,974
|
Yes
|
output
| 1
| 99,487
| 0
| 198,975
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
Submitted Solution:
```
import math
n, k = map(int, input().split())
s = input()
j = -1
cnt = 0
for i in range(1, n + 1):
if i > (n - i):
break
if s[:i] == s[n - i:]:
cnt = i
otv = ''
for i in range(k):
if i % 2 == 0:
otv += s
else:
otv += s[cnt:n - cnt]
if s.count(s[0]) == n:
print(s[0] * k + s[0] * (n - 1))
if k % 2 == 0:
print(otv + s[:cnt])
else:
cnt = 0
for i in range(len(otv)):
if otv[i: i + n] == s:
cnt += 1
if cnt == k:
print(otv[:i + n])
break
```
|
instruction
| 0
| 99,488
| 0
| 198,976
|
No
|
output
| 1
| 99,488
| 0
| 198,977
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
Submitted Solution:
```
n, k = map(int, input().split(' '))
t = input()
sim = []
# split in two halves
left = t[:len(t) // 2]
if len(t) // 2 != 0:
right = t[len(t) // 2 + 1:]
else:
right = t[len(t) // 2:]
# check if t has similar start and end
for i in range(len(left)):
if left[:len(left)-i] == right[i:]:
sim = right[i:]
print(sim)
if sim == []:
print(k * t)
else:
if len(t) % len(sim) == 0 and sim * (len(t) // len(sim)) == t:
print(t + sim * (k-1))
else:
print(k * (sim + t[len(sim):t.rfind(sim)]) + sim)
```
|
instruction
| 0
| 99,489
| 0
| 198,978
|
No
|
output
| 1
| 99,489
| 0
| 198,979
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
Submitted Solution:
```
n, k = [int(el) for el in input().split(' ')]
t = input()
val = -1
for i in range(int(n/2)):
if t[:i+1] == t[(n-i-1):]:
val = i
s = str()
if val is -1:
for j in range(k):
s += t
else:
s = t
for j in range(k-1):
s += t[i+1:]
print(s)
```
|
instruction
| 0
| 99,490
| 0
| 198,980
|
No
|
output
| 1
| 99,490
| 0
| 198,981
|
Evaluate the correctness of the submitted Python 3 solution to the coding contest problem. Provide a "Yes" or "No" response.
You are given a string t consisting of n lowercase Latin letters and an integer number k.
Let's define a substring of some string s with indices from l to r as s[l ... r].
Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Input
The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.
The second line of the input contains the string t consisting of exactly n lowercase Latin letters.
Output
Print such string s of minimum possible length that there are exactly k substrings of s equal to t.
It is guaranteed that the answer is always unique.
Examples
Input
3 4
aba
Output
ababababa
Input
3 2
cat
Output
catcat
Submitted Solution:
```
n,m=map(int,input().split())
w=input()
if w[0]==w[-1]:
w+=w[1:]*(m-1)
else:
w=w*m
print(w)
```
|
instruction
| 0
| 99,491
| 0
| 198,982
|
No
|
output
| 1
| 99,491
| 0
| 198,983
|
Provide tags and a correct Python 3 solution for this coding contest problem.
One of the most important products of the R1 company is a popular @r1.com mail service. The R1 mailboxes receive and send millions of emails every day.
Today, the online news thundered with terrible information. The R1 database crashed and almost no data could be saved except for one big string. The developers assume that the string contains the letters of some users of the R1 mail. Recovering letters is a tedious mostly manual work. So before you start this process, it was decided to estimate the difficulty of recovering. Namely, we need to calculate the number of different substrings of the saved string that form correct e-mail addresses.
We assume that valid addresses are only the e-mail addresses which meet the following criteria:
* the address should begin with a non-empty sequence of letters, numbers, characters '_', starting with a letter;
* then must go character '@';
* then must go a non-empty sequence of letters or numbers;
* then must go character '.';
* the address must end with a non-empty sequence of letters.
You got lucky again and the job was entrusted to you! Please note that the substring is several consecutive characters in a string. Two substrings, one consisting of the characters of the string with numbers l1, l1 + 1, l1 + 2, ..., r1 and the other one consisting of the characters of the string with numbers l2, l2 + 1, l2 + 2, ..., r2, are considered distinct if l1 ≠ l2 or r1 ≠ r2.
Input
The first and the only line contains the sequence of characters s1s2... sn (1 ≤ n ≤ 106) — the saved string. It is guaranteed that the given string contains only small English letters, digits and characters '.', '_', '@'.
Output
Print in a single line the number of substrings that are valid e-mail addresses.
Examples
Input
gerald.agapov1991@gmail.com
Output
18
Input
x@x.x@x.x_e_@r1.com
Output
8
Input
a___@1.r
Output
1
Input
.asd123__..@
Output
0
Note
In the first test case all the substrings that are correct e-mail addresses begin from one of the letters of the word agapov and end in one of the letters of the word com.
In the second test case note that the e-mail x@x.x is considered twice in the answer. Note that in this example the e-mail entries overlap inside the string.
|
instruction
| 0
| 99,756
| 0
| 199,512
|
Tags: implementation
Correct Solution:
```
from sys import stdin, stdout, setrecursionlimit
input = stdin.readline
# setrecursionlimit(int(1e6))
inf = float('inf')
from functools import cmp_to_key
from collections import defaultdict as dd
from collections import Counter, deque
from heapq import *
import math
from math import floor, ceil, sqrt
def geti(): return map(int, input().strip().split())
def getl(): return list(map(int, input().strip().split()))
def getis(): return map(str, input().strip().split())
def getls(): return list(map(str, input().strip().split()))
def gets(): return input().strip()
def geta(): return int(input())
def print_s(s): stdout.write(s+'\n')
def solve():
s = gets()
before = after = 0
n = len(s)
i = 0
ans = 0
while i < n:
while i < n and s[i] != '@':
if s[i].isalpha():
before += 1
if s[i] == '.':
before = 0
i += 1
# print('b', before)
if i < n and s[i] == '@':
i += 1
ok = True
temp = 0
good = False
while i < n and s[i] != '.':
if s[i] == '_' or s[i] == '@':
ok = False
break
if s[i].isalpha():
temp += 1
i += 1
good = True
if not ok or not good:
before = temp
after = 0
continue
if i < n and s[i] == '.':
i += 1
while i < n and s[i].isalpha():
after += 1
i += 1
# print('a', after)
ans += before * after
before = after
after = 0
print(ans)
if __name__=='__main__':
solve()
```
|
output
| 1
| 99,756
| 0
| 199,513
|
Provide tags and a correct Python 3 solution for this coding contest problem.
Max wants to buy a new skateboard. He has calculated the amount of money that is needed to buy a new skateboard. He left a calculator on the floor and went to ask some money from his parents. Meanwhile his little brother Yusuf came and started to press the keys randomly. Unfortunately Max has forgotten the number which he had calculated. The only thing he knows is that the number is divisible by 4.
You are given a string s consisting of digits (the number on the display of the calculator after Yusuf randomly pressed the keys). Your task is to find the number of substrings which are divisible by 4. A substring can start with a zero.
A substring of a string is a nonempty sequence of consecutive characters.
For example if string s is 124 then we have four substrings that are divisible by 4: 12, 4, 24 and 124. For the string 04 the answer is three: 0, 4, 04.
As input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use gets/scanf/printf instead of getline/cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java.
Input
The only line contains string s (1 ≤ |s| ≤ 3·105). The string s contains only digits from 0 to 9.
Output
Print integer a — the number of substrings of the string s that are divisible by 4.
Note that the answer can be huge, so you should use 64-bit integer type to store it. In C++ you can use the long long integer type and in Java you can use long integer type.
Examples
Input
124
Output
4
Input
04
Output
3
Input
5810438174
Output
9
|
instruction
| 0
| 99,861
| 0
| 199,722
|
Tags: dp
Correct Solution:
```
string=input()
n=len(string)
ans=0
for i in range(n-1):
if int(string[i])%4==0:
ans+=1
temp=string[i:i+2]
if temp[0]=='0':
temp=string[i+1]
if(int(temp)%4==0):
ans=ans+i+1
if(int(string[-1])%4==0):
ans=ans+1
print(ans)
```
|
output
| 1
| 99,861
| 0
| 199,723
|
Provide tags and a correct Python 3 solution for this coding contest problem.
Max wants to buy a new skateboard. He has calculated the amount of money that is needed to buy a new skateboard. He left a calculator on the floor and went to ask some money from his parents. Meanwhile his little brother Yusuf came and started to press the keys randomly. Unfortunately Max has forgotten the number which he had calculated. The only thing he knows is that the number is divisible by 4.
You are given a string s consisting of digits (the number on the display of the calculator after Yusuf randomly pressed the keys). Your task is to find the number of substrings which are divisible by 4. A substring can start with a zero.
A substring of a string is a nonempty sequence of consecutive characters.
For example if string s is 124 then we have four substrings that are divisible by 4: 12, 4, 24 and 124. For the string 04 the answer is three: 0, 4, 04.
As input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use gets/scanf/printf instead of getline/cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java.
Input
The only line contains string s (1 ≤ |s| ≤ 3·105). The string s contains only digits from 0 to 9.
Output
Print integer a — the number of substrings of the string s that are divisible by 4.
Note that the answer can be huge, so you should use 64-bit integer type to store it. In C++ you can use the long long integer type and in Java you can use long integer type.
Examples
Input
124
Output
4
Input
04
Output
3
Input
5810438174
Output
9
|
instruction
| 0
| 99,862
| 0
| 199,724
|
Tags: dp
Correct Solution:
```
# Anuneet Anand
s = input()
n = len(s)
D = set()
for i in range(100):
if i%4==0:
x = str(i)
if i<10:
x = "0"+x
D.add(x)
c = 0
for i in range(n-1):
if s[i]+s[i+1] in D:
c = c+i+1
for i in range(n):
if int(s[i])%4==0:
c = c+1
print(c)
```
|
output
| 1
| 99,862
| 0
| 199,725
|
Provide tags and a correct Python 3 solution for this coding contest problem.
Max wants to buy a new skateboard. He has calculated the amount of money that is needed to buy a new skateboard. He left a calculator on the floor and went to ask some money from his parents. Meanwhile his little brother Yusuf came and started to press the keys randomly. Unfortunately Max has forgotten the number which he had calculated. The only thing he knows is that the number is divisible by 4.
You are given a string s consisting of digits (the number on the display of the calculator after Yusuf randomly pressed the keys). Your task is to find the number of substrings which are divisible by 4. A substring can start with a zero.
A substring of a string is a nonempty sequence of consecutive characters.
For example if string s is 124 then we have four substrings that are divisible by 4: 12, 4, 24 and 124. For the string 04 the answer is three: 0, 4, 04.
As input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use gets/scanf/printf instead of getline/cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java.
Input
The only line contains string s (1 ≤ |s| ≤ 3·105). The string s contains only digits from 0 to 9.
Output
Print integer a — the number of substrings of the string s that are divisible by 4.
Note that the answer can be huge, so you should use 64-bit integer type to store it. In C++ you can use the long long integer type and in Java you can use long integer type.
Examples
Input
124
Output
4
Input
04
Output
3
Input
5810438174
Output
9
|
instruction
| 0
| 99,863
| 0
| 199,726
|
Tags: dp
Correct Solution:
```
s = [int(x) for x in input()]
ans = 0
if s[0] % 4 == 0:
ans += 1
for i in range(1, len(s)):
if s[i] % 4 == 0:
ans += 1
if (s[i] + 10 * s[i - 1]) % 4 == 0:
ans += i
print(ans)
```
|
output
| 1
| 99,863
| 0
| 199,727
|
Provide tags and a correct Python 3 solution for this coding contest problem.
Max wants to buy a new skateboard. He has calculated the amount of money that is needed to buy a new skateboard. He left a calculator on the floor and went to ask some money from his parents. Meanwhile his little brother Yusuf came and started to press the keys randomly. Unfortunately Max has forgotten the number which he had calculated. The only thing he knows is that the number is divisible by 4.
You are given a string s consisting of digits (the number on the display of the calculator after Yusuf randomly pressed the keys). Your task is to find the number of substrings which are divisible by 4. A substring can start with a zero.
A substring of a string is a nonempty sequence of consecutive characters.
For example if string s is 124 then we have four substrings that are divisible by 4: 12, 4, 24 and 124. For the string 04 the answer is three: 0, 4, 04.
As input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use gets/scanf/printf instead of getline/cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java.
Input
The only line contains string s (1 ≤ |s| ≤ 3·105). The string s contains only digits from 0 to 9.
Output
Print integer a — the number of substrings of the string s that are divisible by 4.
Note that the answer can be huge, so you should use 64-bit integer type to store it. In C++ you can use the long long integer type and in Java you can use long integer type.
Examples
Input
124
Output
4
Input
04
Output
3
Input
5810438174
Output
9
|
instruction
| 0
| 99,864
| 0
| 199,728
|
Tags: dp
Correct Solution:
```
s=input()
c=0
for i in s:
if int(i)%4==0:
c+=1
for i in range(len(s)-1):
if int(s[i]+s[i+1])%4==0:
c+=(i+1)
print(c)
```
|
output
| 1
| 99,864
| 0
| 199,729
|
Provide tags and a correct Python 3 solution for this coding contest problem.
Max wants to buy a new skateboard. He has calculated the amount of money that is needed to buy a new skateboard. He left a calculator on the floor and went to ask some money from his parents. Meanwhile his little brother Yusuf came and started to press the keys randomly. Unfortunately Max has forgotten the number which he had calculated. The only thing he knows is that the number is divisible by 4.
You are given a string s consisting of digits (the number on the display of the calculator after Yusuf randomly pressed the keys). Your task is to find the number of substrings which are divisible by 4. A substring can start with a zero.
A substring of a string is a nonempty sequence of consecutive characters.
For example if string s is 124 then we have four substrings that are divisible by 4: 12, 4, 24 and 124. For the string 04 the answer is three: 0, 4, 04.
As input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use gets/scanf/printf instead of getline/cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java.
Input
The only line contains string s (1 ≤ |s| ≤ 3·105). The string s contains only digits from 0 to 9.
Output
Print integer a — the number of substrings of the string s that are divisible by 4.
Note that the answer can be huge, so you should use 64-bit integer type to store it. In C++ you can use the long long integer type and in Java you can use long integer type.
Examples
Input
124
Output
4
Input
04
Output
3
Input
5810438174
Output
9
|
instruction
| 0
| 99,865
| 0
| 199,730
|
Tags: dp
Correct Solution:
```
s = input()
c = 0
for i in s:
if(int(i) % 4 == 0):
c += 1
i, j = len(s) - 1, len(s) - 2
while(j >= 0):
if(int(''.join(s[j : i + 1])) % 4 == 0):
c += len(s) - (len(s) - j) + 1
# print(i, j)
i -= 1
j -= 1
print(c)
```
|
output
| 1
| 99,865
| 0
| 199,731
|
Provide tags and a correct Python 3 solution for this coding contest problem.
Max wants to buy a new skateboard. He has calculated the amount of money that is needed to buy a new skateboard. He left a calculator on the floor and went to ask some money from his parents. Meanwhile his little brother Yusuf came and started to press the keys randomly. Unfortunately Max has forgotten the number which he had calculated. The only thing he knows is that the number is divisible by 4.
You are given a string s consisting of digits (the number on the display of the calculator after Yusuf randomly pressed the keys). Your task is to find the number of substrings which are divisible by 4. A substring can start with a zero.
A substring of a string is a nonempty sequence of consecutive characters.
For example if string s is 124 then we have four substrings that are divisible by 4: 12, 4, 24 and 124. For the string 04 the answer is three: 0, 4, 04.
As input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use gets/scanf/printf instead of getline/cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java.
Input
The only line contains string s (1 ≤ |s| ≤ 3·105). The string s contains only digits from 0 to 9.
Output
Print integer a — the number of substrings of the string s that are divisible by 4.
Note that the answer can be huge, so you should use 64-bit integer type to store it. In C++ you can use the long long integer type and in Java you can use long integer type.
Examples
Input
124
Output
4
Input
04
Output
3
Input
5810438174
Output
9
|
instruction
| 0
| 99,866
| 0
| 199,732
|
Tags: dp
Correct Solution:
```
s=input()
a=[0]
count=0
ans=0
for i in range(1,len(s)):
p=int(s[i-1]+s[i])
#print(p)
if(p%4==0):
a.append(1)
else:
a.append(0)
#print(a)
for i in range(len(a)):
if(a[i]==1):
count=count+i
for i in s:
if(int(i)%4==0):
ans+=1
output=count+ans
#print(count)
#print(ans)
print(output)
```
|
output
| 1
| 99,866
| 0
| 199,733
|
Provide tags and a correct Python 3 solution for this coding contest problem.
Max wants to buy a new skateboard. He has calculated the amount of money that is needed to buy a new skateboard. He left a calculator on the floor and went to ask some money from his parents. Meanwhile his little brother Yusuf came and started to press the keys randomly. Unfortunately Max has forgotten the number which he had calculated. The only thing he knows is that the number is divisible by 4.
You are given a string s consisting of digits (the number on the display of the calculator after Yusuf randomly pressed the keys). Your task is to find the number of substrings which are divisible by 4. A substring can start with a zero.
A substring of a string is a nonempty sequence of consecutive characters.
For example if string s is 124 then we have four substrings that are divisible by 4: 12, 4, 24 and 124. For the string 04 the answer is three: 0, 4, 04.
As input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use gets/scanf/printf instead of getline/cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java.
Input
The only line contains string s (1 ≤ |s| ≤ 3·105). The string s contains only digits from 0 to 9.
Output
Print integer a — the number of substrings of the string s that are divisible by 4.
Note that the answer can be huge, so you should use 64-bit integer type to store it. In C++ you can use the long long integer type and in Java you can use long integer type.
Examples
Input
124
Output
4
Input
04
Output
3
Input
5810438174
Output
9
|
instruction
| 0
| 99,867
| 0
| 199,734
|
Tags: dp
Correct Solution:
```
s = input()
count=0
if int(s[0])%4==0:
count+=1
for i in range(1,len(s)):
if int(s[i-1])%2==0 and (s[i] in '048'):
count+=(i+1)
elif int(s[i-1])%2==1 and s[i] in '26':
count+=i
elif int(s[i])%4==0:
count+=1
print(count)
```
|
output
| 1
| 99,867
| 0
| 199,735
|
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