Problem:


Score : 200 points

Problem Statement

Given are strings s and t of length N each, both consisting of lowercase English letters.

Let us form a new string by alternating the characters of S and the characters of T, as follows: the first character of S, the first character of T, the second character of S, the second character of T, ..., the N-th character of S, the N-th character of T. Print this new string.

Constraints

1 \leq N \leq 100

|S| = |T| = N

S and T are strings consisting of lowercase English letters.

Input

Input is given from Standard Input in the following format:

N
S T

Output

Print the string formed.

Sample Input 1

2
ip cc

Sample Output 1

icpc

Sample Input 2

8
hmhmnknk uuuuuuuu

Sample Output 2

humuhumunukunuku

Sample Input 3

5
aaaaa aaaaa

Sample Output 3

aaaaaaaaaa



Sample input:
2
ip cc


Sample output:
icpc

Submission status: Accepted

Solution code:
n=int(input())
s,t=input().split(" ")
u=""
for i in range(n):
  u = u + s[i] + t[i]
print(u)

Submission status: Accepted

Solution code:
n = int(input())
s,t = input().split()
new = ''
for i in range(n):
  new += s[i]
  new += t[i]
print (new)

Submission status: Accepted

Solution code:
n=int(input())
s,t=input().split()
ans = [0]*(2*n)
ans[::2] = s
ans[1::2] = t
print("".join(ans))

Submission status: Accepted

Solution code:
N = int(input())
S,T = input().split()
ans = ''
for s,t in zip(S,T):
    ans += s
    ans += t
print(ans)

Submission status: Accepted

Solution code:
n = int(input())
s,t = map(str,input().split())
ans = []
for i in range(n):
    ans.append(s[i])
    ans.append(t[i])
print("".join(ans))

Submission status: Accepted

Solution code:
n = int(input())
s = input()
print("".join([s[((n+1)*i)%(2*n+1)] for i in range(0,2*n)]))

Submission status: Accepted

Solution code:
import math
from math import ceil
from math import factorial
from collections import Counter
from operator import itemgetter
import bisect
ii = lambda: int(input())
iia = lambda: list(map(int,input().split()))
isa = lambda: list(input().split())

n = ii()
a,b = input().split()
c = ''

for i in range(n):
	c+=(a[i]+b[i])
print(c)

Submission status: Accepted

Solution code:
N=int(input())
S, T = input().split()

for i in range(N):
  print(S[i]+T[i], end='')
print()

Submission status: Accepted

Solution code:
input()
s1, s2 = input().split()
for a, b in zip(s1, s2):
  print(a+b, end='')

Submission status: Accepted

Solution code:
n=int(input())
st=input().split()
s=list(st[0])
t=list(st[1])
ans=[]
for i in range(n):
    ans.append(s[i])
    ans.append(t[i])
print(''.join(ans))

Submission status: Accepted

Solution code:
n = int(input())
s, t = input().split()
for i in range(n):
    print(s[i], end = '')
    print(t[i], end = '')

Submission status: Accepted

Solution code:
n = int(input())
s,t = input().split()

ans = ""
for i in range(n):
  ans += (s[i] + t[i])
  
print(ans)

Submission status: Accepted

Solution code:
N = int(input())
s,t = map(str,input().split())
ans = ""
for i in range(N):
  ans+=s[i]
  ans+=t[i]
print(ans)

Submission status: Accepted

Solution code:
n = int(input())
s, t = input().split()

ans = ""
for i in range(n):
  ans += (s[i] + t[i])
  
print(ans)

Submission status: Accepted

Solution code:
n = int(input())
s, t = map(list, input().split())
ans = ""
for i in range(n):
 ans += s[i] + t[i]

print(ans)

Submission status: Accepted

Solution code:
n = int(input())
s, t = input().split(" ")
ans = ""
for i in range(n):
    ans += s[i]
    ans += t[i]
print(ans)

Submission status: Accepted

Solution code:
#!/usr/bin/env python3
import sys
sys.setrecursionlimit(10000000)
INF = 1<<32


def solve(N: int, S: str, T: str):
    ans = []
    for i in range(N):
        ans.append(S[i])
        ans.append(T[i])

    print(''.join(ans))
    return



def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  # type: int
    S = next(tokens)  # type: str
    T = next(tokens)  # type: str
    solve(N, S, T)

if __name__ == '__main__':
    main()

Submission status: Accepted

Solution code:
N=int(input())
S,T=input().split()

print(''.join([S[i]+T[i] for i in range(N)]))

Submission status: Accepted

Solution code:
n = int(input())
s, t = map(list, input().split(' '))

ans = ''
for i in range(n):
    ans = ans + str(s[i])+str(t[i])

print(ans)

Submission status: Accepted

Solution code:
N = int(input())
S,T=map(str,input().split())

cnt = 0
ans = ""

for cnt in range(N):
  ans=ans+S[cnt]+T[cnt]
  
print(ans)

Submission status: Accepted

Solution code:
N = int(input())
s, t = input().split()

new = list()
for i in range(N):
  new.append(s[i])
  new.append(t[i])
  
print(*new, sep='')

Submission status: Accepted

Solution code:
n = int(input())
s, t = input().split()

for i, j in zip(s, t):
  print(i+j, end='')
  
print()

Submission status: Accepted

Solution code:
n = int(input())
s,t = map(str, input().split())
res = ""
for i in range(n):
    res += s[i:i+1] + t[i:i+1]
print(res)

Submission status: Accepted

Solution code:
n = int(input())
a ,b = input().split(" ")
s = ""
for x in range(n):
  s = s + a[x] + b[x]
print(s)

Submission status: Accepted

Solution code:
input()
a,b = input().split()

for ta,tb in zip(a,b):
	print(ta, end="")
	print(tb, end="")
print()

Submission status: Accepted

Solution code:
n = int(input())
s, t = [elem for elem in input().split()]

res = ""
for i, j in zip(s, t):
  res += i
  res += j
print(res)

Submission status: Accepted

Solution code:
N = int(input())
S, T = map(str,input().split())

ans = ""
for i in range(N):
  ans += S[i]
  ans += T[i]
print(ans)

Submission status: Accepted

Solution code:
n=int(input())
words=[i for i in input().split()]
A=list(words[0])
B=list(words[1])

for j in range(n):
    print(A[j],end="")
    print(B[j],end="")

Submission status: Accepted

Solution code:
import sys

n = int(input())
s = input().split()
answer = ''

for i in range(n):
    answer += s[0][i]
    answer += s[1][i]

print(answer)

Submission status: Accepted

Solution code:
N = int(input())
S, T = input().split()
string = ""
for i in range(N):
	string += S[i]
	string += T[i]
else:
	print(string)

Submission status: Accepted

Solution code:
n = input()
a, b = input().split()
for i, j in zip(a, b):
  print(i, end="")
  print(j, end="")
print()

Submission status: Accepted

Solution code:
n = int(input())
a,b= map(str,input().split())
for i in range(n):
  print(a[i]+b[i],end="")

Submission status: Accepted

Solution code:
n = int(input())
w, x = input().split(" ")
s = str(w)
t = str(x)

new_str = ""

for i in range(0, n):
    new_str += s[i]
    new_str += t[i]

print(new_str)

Submission status: Accepted

Solution code:
N=int(input())
S=input()
print(''.join([S[i]+S[i+N+1] for i in range(N)]))

Submission status: Accepted

Solution code:
N = int(input())
A, B = input().split()

ans = ''
for i in range(N):
  ans += A[i] + B[i]
  
print(ans)

Submission status: Accepted

Solution code:
N = int(input())
Str_input = str(input())
S = Str_input.split()[0]
T = Str_input.split()[1]
ans = ''
for i in range(N):
    ans = ans + S[i:i+1] + T[i:i+1]
print(ans)

Submission status: Accepted

Solution code:
N = int(input())
S, T = raw_input().split()

ret = ''

for n in range(N):
    ret += S[n]
    ret += T[n]

print '{}'.format(ret)

Submission status: Accepted

Solution code:
def main():

    n = int(input())
    S, T = map(str, input().split())

    ans = ''

    for i in range(n):
        ans += S[i]
        ans += T[i]

    print(ans)

if __name__ == "__main__":
    main()

Submission status: Accepted

Solution code:
N = int(input())
S = input().split()
Output = ""
 
for i in range(N) :
  Output = Output + S[0][i] + S[1][i]

print(Output)

Submission status: Accepted

Solution code:

N = int(input())
S,T = input().split()

char = ""
for i in range(0,N):
    char += (S[i] + T[i])

print(char)

Submission status: Accepted

Solution code:
n = int(input())
s, t = input().split()

#print(n, s, t)


ans = ""
for i in range(n):
    ans = ans + s[i] + t[i]

print(ans)

Submission status: Accepted

Solution code:
n=int(input())
s,t=input().split()
i=0
while i<n:
    print(s[i]+t[i],end="")
    i+=1

Submission status: Accepted

Solution code:
N = int(input())
S,T = input().split()

result = ""
for s, t in zip(S, T):
  result += (s + t)

print(result)

Submission status: Accepted

Solution code:
N = int(input())    #文字数
str_list = input().split(" ")

new_str = str_list[0][0] + str_list[1][0]

for i in range(N-1):
	new_str += str_list[0][i+1] + str_list[1][i+1]

print(new_str)

Submission status: Accepted

Solution code:
N = int(input())
S, T = input().split()

print("".join(s+t for s, t in zip(S, T)))

Submission status: Accepted

Solution code:
input()
S, T = map(lambda x: list(x), input().split())
[print("{}{}".format(i, j), end="") for i, j in zip(S, T)]
print()

Submission status: Accepted

Solution code:
def main():

    n = int(input())
    s, t = input().split()

    res = []
    for i in range(n):
        res.append(s[i])
        res.append(t[i])

    print("".join(res))


main()

Submission status: Accepted

Solution code:
n = int(input())
s, t = [_ for _ in input().split()]

for e in zip(s, t):
    print(''.join(e), end='')
print()

Submission status: Accepted

Solution code:
N = int(input())
S, T = input().split()
ans = ""
for s, t in zip(S, T):
    ans += (s + t)
print(ans)

Submission status: Accepted

Solution code:
n = int(input())
s,t = map(str,input().split())

ans = ""

for i in range(n):
    ans = ans + s[i] + t[i]

print(ans)

Submission status: Accepted

Solution code:
n = int(input())
s, t = input().split()
str = ''

for i in range(n):
    str += s[i]+t[i]

print(str)

Submission status: Accepted

Solution code:
n=int(input())
s,t=input().split()
r=''
for i in range(2*n):
	if i%2==0:
		r+=s[i//2]
	else:
		r+=t[i//2]
print(r)

Submission status: Accepted

Solution code:
# coding: utf-8

N = int(input())
S, T = map(str, input().split())
array = []
for i in range(N):
    array.append(S[i])
    array.append(T[i])

for j in range(2 * N):
    print(array[j], end = "")

Submission status: Accepted

Solution code:
N = int(input())
S, T = map(list, input().split())

answer = str()

for i in range(len(T)):
    if S[i] != '':
        answer += str(S[i])
    if T[i] != '':
        answer += str(T[i])

print(answer)

Submission status: Accepted

Solution code:
n = int(input())
s, t = input().split()

for i in range(n):
    print(s[i], end = '')
    print(t[i], end = '')

Submission status: Accepted

Solution code:
#b strings with the same length
n=int(input())
sentence=input().split()
ans=""
for i in range(n):
    ans=ans+sentence[0][i]+sentence[1][i]
print(ans)

Submission status: Accepted

Solution code:
n = int(input())
s, t = input().split(" ")
out_str = ""

for i in range(n):
  out_str += s[i]
  out_str += t[i]

print(out_str)

Submission status: Accepted

Solution code:
a = int(input())
b, c = input().split()
blst = list(str(b))
clst = list(str(c))

x = ""
for i in range(a):
    x += b[i] + c[i]

print(x)

Submission status: Accepted

Solution code:
N=int(input());
S,T=input().split()
for i in range(N):
  print(S[i] + T[i], end='')

Submission status: Accepted

Solution code:
N = int(input())

S,T = input().split()

ans = ""

for i in range(N):
    ans += S[i]
    ans += T[i]

print(ans)

Submission status: Accepted

Solution code:
N = int(input())
S , T = list(input().split())
ans = ''
for i in range(N):
	ans += S[i] + T[i]
print(ans)

Submission status: Accepted

Solution code:
N=int(input())
S,T=map(str,input().split())
ans=""
for i in range(N):
    ans=ans+S[i]+T[i]
print(ans)

Submission status: Accepted

Solution code:
n = int(input())
string = input()
s = string.split(" ")[0]
t = string.split(" ")[1]
new = ""

for i in range(0,n):
    new += s[i] + t[i]

print(new)

Submission status: Accepted

Solution code:
N = input()
line = list(input())

tmp = ['' for _ in range(int(N))]
i = 0 
while len(line) != 0:
    c = line.pop(0)
    if c == ' ':
        i = 0
    else:
        tmp[i] = tmp[i] + c
        i = i + 1

print(''.join(tmp))

Submission status: Accepted

Solution code:
N = int(input())
S, T = map(str, input().split())
S = list(S)
T = list(T)

for i in range(N):
  ans = []
  for j in range(N):
    ans.append(S[j])
    ans.append(T[j])
print(''.join(ans))

Submission status: Accepted

Solution code:
n = int(input())
line = input().split(" ")
 
s = line[0]
t = line[1]
 
for i in range(0, len(s)): 
  print(s[i], end="")
  print(t[i], end="")

Submission status: Accepted

Solution code:
N = int(input())
S, T = input().split()
print("".join([S[i] + T[i] for i in range(N)]))

Submission status: Accepted

Solution code:
N = int(input())
S, T = input().split()
U = ""
for i in range(N):
    U += S[i] + T[i]
print(U)

Submission status: Accepted

Solution code:
N = int(input())
S,T = input().split()
 
Q = ""
for i in range (N):
  Q = Q + S[i] + T[i]
  
print(Q)

Submission status: Accepted

Solution code:
n = int(input())
x = input().split(" ")

for i in range(n):
  for j in x:
    print(j[i],end="")

Submission status: Accepted

Solution code:
n = int(input())
a,b = input().split()

ans = ""
for i in range(n):
    ans = ans + a[i]+b[i]

print(ans)

Submission status: Accepted

Solution code:
n = int(input())
r = input()
s = r.split(" ")[0]
t = r.split(" ")[1]
u = ""

for i in range (n):
  u += s[i]
  u += t[i]
  
print(u)

Submission status: Accepted

Solution code:
N = int(input())
S, T = input().split(" ")
print(''.join([s + t for s, t in zip(S, T)]))

Submission status: Accepted

Solution code:
n = int(input())
s,t = input().split()

str_ans = ''

for i in range(n):
    str_ans += s[i]
    str_ans += t[i]
print(str_ans)

Submission status: Accepted

Solution code:
input()
st=raw_input().split()
a=""
for s,t in zip(st[0],st[1]):
 a+=(s+t)
print(a)

Submission status: Accepted

Solution code:
n = int(input())
s,t = input().split()

string = ''

for i in range(n):
    string = string + s[i]
    string = string + t[i]

print(string)

Submission status: Accepted

Solution code:
n = int(input())

string = input().split()
s = string[0]
t = string[1]

output = ""

for i in range(n):
  output += s[i] + t[i]

print(output)

Submission status: Accepted

Solution code:
n=int(input())
s,t=map(str,input().split())

a=""

for i in range(n):
	a=a+s[i]+t[i]
	
print(a)

Submission status: Accepted

Solution code:
string = []
n = int(input())
a, b = input().split()
for i in range(n):
    string.append(a[i])
    string.append(b[i])

print(''.join(string))

Submission status: Accepted

Solution code:
string = []
n = int(input())
a, b = input().split()
for i in range(n):
  string.append(a[i])
  string.append(b[i])

print(''.join(string))

Submission status: Accepted

Solution code:
import sys
input = sys.stdin.readline
N = int(input())
S, T = input().split()
U = [""]*2*N
for i in range(N):
    U[2*i] = S[i]
    U[2*i+1] = T[i]
print("".join(U))

Submission status: Accepted

Solution code:
N = int(input())
S, T = input().split()

for s, t in zip(S, T):
    print('{}{}'.format(s, t), end='')
print('')

Submission status: Accepted

Solution code:
n = int(input())
s, t = input().split()
 
res = ''
 
for i in range(n):
  res = res + str(s[i]) + str(t[i])
  
print(res)

Submission status: Accepted

Solution code:
N=int(input())
S,T=input().split()

for s,t in zip(S,T):
    print(s+t,end="")

Submission status: Accepted

Solution code:
def main(sample_file = ''):

    """ convenient functions
    # for i, a in enumerate(iterable)
    # q, mod = divmod(a, b)
    # divmod(x, y) returns the tuple (x//y, x%y)
    # Higher-order function: reduce(operator.mul, xyz_count, 1)
    # manage median(s) using two heapq https://atcoder.jp/contests/abc127/tasks/abc127_f
    """

    """convenient decorator
    # @functools.lru_cache():
    # to facilitate use of recursive function
        # ex:
        # from functools import lru_cache
        # import sys
        # sys.setrecursionlimit(10**9)
        # @lru_cache(maxsize=None)
        # def fib(n):
        #     if n < 2:
        #         return n
        #     return fib(n-1) + fib(n-2)
        # print(fib(1000))
    """
    
    # import numpy as np
    import sys
    sys.setrecursionlimit(10**7)
    from itertools import accumulate, combinations, permutations, product # https://docs.python.org/ja/3/library/itertools.html
    # accumulate() returns iterator! to get list: list(accumulate())
    from math import factorial, ceil, floor, sqrt
    def factorize(n):
        """return the factors of the Arg and count of each factor
        
        Args:
            n (long): number to be resolved into factors
        
        Returns:
            list of tuples: factorize(220) returns [(2, 2), (5, 1), (11, 1)]
        """
        fct = []  # prime factor
        b, e = 2, 0  # base, exponent
        while b * b <= n:
            while n % b == 0:
                n = n // b
                e = e + 1
            if e > 0:
                fct.append((b, e))
            b, e = b + 1, 0
        if n > 1:
            fct.append((n, 1))
        return fct
    def combinations_count(n, r):
        """Return the number of selecting r pieces of items from n kinds of items.
        
        Args:
            n (long): number
            r (long): number
        
        Raises:
            Exception: not defined when n or r is negative
        
        Returns:
            long: number
        """
        # TODO: How should I do when n - r is negative?
        if n < 0 or r < 0:
            raise Exception('combinations_count(n, r) not defined when n or r is negative')
        if n - r < r: r = n - r
        if r < 0: return 0
        if r == 0: return 1
        if r == 1: return n
        numerator = [n - r + k + 1 for k in range(r)]
        denominator = [k + 1 for k in range(r)]
        for p in range(2,r+1):
            pivot = denominator[p - 1]
            if pivot > 1:
                offset = (n - r) % p
                for k in range(p-1,r,p):
                    numerator[k - offset] /= pivot
                    denominator[k] /= pivot
        result = 1
        for k in range(r):
            if numerator[k] > 1:
                result *= int(numerator[k])
        return result
    def combinations_with_replacement_count(n, r):
        """Return the number of selecting r pieces of items from n kinds of items allowing individual elements to be repeated more than once.
        
        Args:
            n (long): number
            r (long): number
        
        Raises:
            Exception: not defined when n or r is negative
        
        Returns:
            long: number
        """
        if n < 0 or r < 0:
            raise Exception('combinations_with_replacement_count(n, r) not defined when n or r is negative')
        elif n == 0:
            return 1
        else:
            return combinations_count(n + r - 1, r)
    from bisect import bisect_left, bisect_right
    from collections import deque, Counter, defaultdict # https://docs.python.org/ja/3/library/collections.html#collections.deque
    from heapq import heapify, heappop, heappush, heappushpop, heapreplace,nlargest,nsmallest # https://docs.python.org/ja/3/library/heapq.html
    from copy import deepcopy, copy # https://docs.python.org/ja/3/library/copy.html
    import operator
    from operator import itemgetter #sort 
    # ex1: List.sort(key=itemgetter(1))
    # ex2: sorted(tuples, key=itemgetter(1,2))
    from functools import reduce, lru_cache
    def chmin(x, y):
        """change minimum
        if x > y, x = y and return (x, True).
        convenient when solving problems of dp[i]
        
        Args:
            x (long): current minimum value
            y (long): potential minimum value
        
        Returns:
            (x, bool): (x, True) when updated, else (x, False)
        """
        if x > y:
            x = y
            return (x, True)
        else:
            return (x, False)
    def chmax(x, y):
        """change maximum
        if x < y, x = y and return (x, True).
        convenient when solving problems of dp[i]
        
        Args:
            x (long): current maximum value
            y (long): potential maximum value
        
        Returns:
            (x, bool): (x, True) when updated, else (x, False)
        """
        if x < y:
            x = y
            return (x, True)
        else:
            return (x, False)

    from fractions import gcd # Deprecated since version 3.5: Use math.gcd() instead.
    def gcds(numbers):
        return reduce(gcd, numbers)
    def lcm(x, y):
        return (x * y) // gcd(x, y)
    def lcms(numbers):
        return reduce(lcm, numbers, 1)
    def make_divisors(n, reversed=False):
        """create list of divisors
        
        Args:
            number (int): number from which list of divisors is created
            reversed (bool, optional): ascending order if False. Defaults to False.
        
        Returns:
            list: list of divisors
        """
        divisors = set()
        for i in range(1, int(n**0.5)+1):
            if n % i == 0:
                divisors.add(i)
                divisors.add(n//i)
        return sorted(list(divisors),reverse=reversed)
    
    # first create factorial_list
    # fac_list = mod_factorial_list(n)
    INF = 10 ** 18
    MOD = 10 ** 9 + 7
    modpow = lambda a, n, p = MOD: pow(a, n, p) # Recursive function in python is slow!
    def modinv(a, p = MOD):
        # evaluate reciprocal using Fermat's little theorem:
        # a**(p-1) is identical to 1 (mod p) when a and p is coprime
        return modpow(a, p-2, p)
    def modinv_list(n, p = MOD):
        if n <= 1:
            return [0,1][:n+1]
        else:
            inv_t = [0,1]
            for i in range(2, n+1):
                inv_t += [inv_t[p % i] * (p - int(p / i)) % p]
            return inv_t
    def modfactorial_list(n, p = MOD):
        if n == 0:
            return [1]
        else:
            l = [0] * (n+1)
            tmp = 1
            for i in range(1, n+1):
                tmp = tmp * i % p
                l[i] = tmp
            return l
    def modcomb(n, k, fac_list = [], p = MOD):
        # fac_list = modfactorial_list(100)
        # print(modcomb(100, 5, modfactorial_list(100)))
        from math import factorial
        if n < 0 or k < 0 or n < k: return 0
        if n == 0 or k == 0: return 1
        if len(fac_list) <= n:
            a = factorial(n) % p
            b = factorial(k) % p
            c = factorial(n-k) % p
        else:
            a = fac_list[n]
            b = fac_list[k]
            c = fac_list[n-k]
        return (a * modpow(b, p-2, p) * modpow(c, p-2, p)) % p
    def modadd(a, b, p = MOD):
        return (a + b) % MOD
    def modsub(a, b, p = MOD):
        return (a - b) % p
    def modmul(a, b, p = MOD):
        return ((a % p) * (b % p)) % p
    def moddiv(a, b, p = MOD):
        return modmul(a, modpow(b, p-2, p))

    class UnionFindTree:
        """union find tree class
        TODO: fix this description...
        how to use (example):
        >>  uf = UnionFindTree(N) 
        >>  if uf.find_root(a) == uf.find_root(b):
        >>      do something
        >>  else:
        >>      do something
        >>      uf.unite(a, b)
        """
        def __init__(self, N):
            self.root = [-1] * (N+1)
            self.rank   = [0]  * (N+1)
            self.connected_num = [1] * (N+1)
    
        def find_root(self,x):
            root = self.root
            while root[x] != -1:
                x = root[x]
            return x
    
        def unite(self,x,y):
            root = self.root
            rank = self.rank
            connected_num = self.connected_num
            find_root = self.find_root
    
            rx = find_root(x)
            ry = find_root(y)
            if rx != ry:
                if rank[rx] < rank[ry]:
                    root[rx] = ry
                    rx,ry = ry,rx
                else:
                    if rank[rx] == rank[ry]:
                        rank[rx] += 1
                    root[ry] = rx       
                connected_num[rx] += connected_num[ry]

    # Graph: https://en.wikipedia.org/wiki/Directed_graph
    # Bellman-Ford: O(|V||E|). Use this if there exists an edge with negative length in the graph
    # After N steps, the shortest path has converded if there doesn't exist an cycle of edges with negative
    # Watch out: d[N] == d[2*N] doesn't necessarily mean the graph doesn't have negative cycle
    # ref: https://www.youtube.com/watch?v=1Z6ofKN03_Y

    def BellmanFord(N, M, ABC, vertex_start, vertex_end, value_if_inf = -1, find_shortest = False):
        """to calculate furthest or shortest length between vertex_start and vertex_end using BellmanFord algorithm
        
        Args:
            N (int): number of vertices
            M (int): number of edges
            ABC (list): [(ai, bi, ci) for _ in range(N)] where i-th edge is directed from vertex ai to vertex bi and the length is ci 
            vertex_start (int): start vertex. usually use 0.
            vertex_end (int): end vertex. usually use N-1.
            value_if_inf (int or string as you like, optional): value you want when the furthest (or shortest) distance is infinite (or -infinite). Defaults to -1.
            find_shortest (bool, optional): choose False to find furthest path. Defaults to False.
        
        Returns:
            int or string: normally int (but can be str if you set value_if_inf to str)
            
        Example:
                N, M, P = R()
                ABC = [R() for _ in range(M)]
                ABC = [(a-1, b-1, c-P) for a, b, c in ABC]
                print(BellmanFord(N, M, ABC, 0, N-1, value_if_inf = 'inf'))

        """

        def make_reachable_list(N, M, ABC, vertex_start, vertex_end):
            reachable_to_direct = defaultdict(list)
            reachable_from_direct = defaultdict(list)
            reachable_from_start = [False] * N
            reachable_to_end = [False] * N
            reachable_from_start[vertex_start] = True
            reachable_to_end[vertex_end] = True
            reachable_from_both_sides = [False] * N
            dfs_from_start = []
            dfs_to_end = []
            for a, b, c in ABC:
                reachable_to_direct[a].append(b)
                reachable_from_direct[b].append(a)
                if a == vertex_start:
                    dfs_from_start.append(b)
                    reachable_from_start[b] = True
                if b == vertex_end:
                    dfs_to_end.append(a)
                    reachable_to_end[a] = True
            while dfs_from_start:
                v = dfs_from_start.pop()
                for i in reachable_to_direct[v]:
                    if not reachable_from_start[i]:
                        reachable_from_start[i] = True
                        dfs_from_start.append(i)
            while dfs_to_end:
                v = dfs_to_end.pop()
                for i in reachable_from_direct[v]:
                    if not reachable_to_end[i]:
                        reachable_to_end[i] = True
                        dfs_to_end.append(i)
            for i in range(N):
                reachable_from_both_sides[i] = reachable_from_start[i] and reachable_to_end[i]
            return reachable_from_both_sides
        
        reachable_from_both_sides = make_reachable_list(N, M, ABC, vertex_start, vertex_end)
        
        if find_shortest:
            dist = [INF for i in range(N)]
        else:
            dist = [-INF for i in range(N)]
        
        dist[vertex_start] = 0
        for i in range(N):
            updated = False
            for a, b, c in ABC:
                if not reachable_from_both_sides[a]:
                    continue
                elif find_shortest:
                    update_condition = dist[a] + c < dist[b]
                else:
                    update_condition = dist[a] + c > dist[b]
                if dist[a] != INF and update_condition:
                    dist[b] = dist[a] + c
                    updated = True
                    if i == N-1:
                        return value_if_inf
            if not updated:
                break
        return dist[vertex_end]

    """ initialize variables and set inputs
    # initialize variables
        # to initialize list, use [0] * n
        # to initialize two dimentional array:
            # ex) [[0] * N for _ in range(N)]
            # ex2) dp = [[0] * (N+1) for _ in range(W*2)]
    # set inputs
        # put inputs between specific values (almost as quickly)
        # ex) S = [-INF] + [int(r()) for _ in range(A)] + [INF]
        # open(0).read() is sometimes useful:
        # ex) n, m, *x = map(int, open(0).read().split())
        #     min(x[::2]) - max(x[1::2])
        # ex2) *x, = map(int, open(0).read().split())
        #     don't forget to add comma after *x if only one variable is used
    # preprocessing
        # transpose = [x for x in zip(*data)]
        # ex) [[1, 2, 3], [4, 5, 6], [7, 8, 9]] => [(1, 4, 7), (2, 5, 8), (3, 6, 9)]
        # flat = [flatten for inner in data for flatten in inner]
        # ex) [[1, 2, 3], [4, 5, 6], [7, 8, 9]] => [1, 2, 3, 4, 5, 6, 7, 8, 9]
    # calculate and output
        # output pattern
        # ex1) print(*l) => when l = [2, 5, 6], printed 2 5 6
    """

    # functions to read input
    r = lambda: sys.stdin.readline().strip()
    r_int = lambda: int(r())
    r_float = lambda: float(r())
    R = lambda: list(map(int, r().split()))
    R_map = lambda: map(int, r().split())
    R_float = lambda: list(map(float, r().split()))
    R_tuple = lambda: tuple(map(int, r().split()))

    """ how to treat input
    # single int: int(r())
    # single string: r()
    # single float: float(r())
    # line int: R()
    # line string: r().split()
    # line (str, int, int): [j if i == 0 else int(j) for i, j in enumerate(r().split())]
    # lines int: [R() for _ in range(n)]
    """

    # for test
    if sample_file:
        sys.stdin = open(sample_file)
        
    # ----------------------------------
    # main

    N = r_int()
    S, T = r().split()
    for (i, j) in zip(S, T):
        print(i, j, sep="", end="")
    print()
    
    # to finish code, use return instead of exit()
    # end of main
    # ----------------------------------

    """memo: how to use defaultdict of list
    # initialize
    Dic = defaultdict(list)
    # append / extend
    Dic[x].append(y)
    # three methods for loop: keys(), values(), items()
    for k, v in Dic.items():
    """
    
    """memo: how to solve binary problems
    # to make binary digits text
    >>> a = 5
    >>> bin_str_a = format(a, '#06b')
    >>> print(bin_str_a)
    0b0101 # first 2 strings (='0b') indicates it is binary
    """
    
    """memo: how to solve the problem
    creating simple test/answer
    greed
    simple dp
    graph
    """

if __name__ == '__main__':
    main()

Submission status: Accepted

Solution code:
n = int(input())
S,T = input().split()
res = ""
for i in range(n) :
    res += S[i] + T[i]
print(res)

Submission status: Accepted

Solution code:
n = int(input())
s,t = map(str,input().split())

new_s = ""
for i in range(n):
    new_s = new_s + str(s[i]) + str(t[i])

print(new_s)

Submission status: Accepted

Solution code:
N = int(input())
S, T = map(str, input().split())
sum = ""
for i in range(N):
    sum = sum + S[i] + T[i]
print(sum)

Submission status: Accepted

Solution code:
n = int(input())
s, t = input().split()

r = ""

for i in range(n):
  r += s[i] + t[i]

print(r)

Submission status: Accepted

Solution code:
n = int(input())
s, t = map(str, list(input().split()))
result = []
for i in range(n):
    result.append(s[i])
    result.append(t[i])
print(''.join(result))