Harryxun/testdata huggingface dataset:
Buggy python submission (verdict: Runtime Error):
H,W,A,B = map(int,input().split())



if H==1:
    if B>0:
        ans = 'No'
    else:
        ans = "0"*A + "1"*(W-A)
elif W==1:
    if A>0:
        ans = 'No'
    else:
        for i in range(B):
            print(1)
        for i in range(H-B):
            print(0)
        exit()
else:
    s = "1"*A + "0"*(W-A)
    if W%A==0 and A!=0 and H%(W/A) == 0 and H/(W/A)==B:
        for i in range(H):
            print(s)
            s = s[A:] + s[:A]
        exit()
    else:ans = 'No'
print(ans)

Fixed submission:
H,W,A,B = map(int,input().split())

s = "0"*A + "1"*(W-A)
for i in range(B):
    print(s)
s = "1"*A + "0"*(W-A)
for i in range(H-B):
    print(s)

Buggy python submission (verdict: Runtime Error):
H,W,A,B = map(int,input().split())
if H==1:
    if B>0:ans = 'No'
    else:ans = "0"*A + "1"*(W-A)
else:
    s = "1"*A + "0"*(W-A)
    if W%A==0 and H%(W/A) == 0 and H/(W/A)==B:

        for i in range(H):
            print(s)
            s = s[A:] + s[:A]
        exit()
    else:ans = 'No'
print(ans)

Fixed submission:
H,W,A,B = map(int,input().split())

s = "0"*A + "1"*(W-A)
for i in range(B):
    print(s)
s = "1"*A + "0"*(W-A)
for i in range(H-B):
    print(s)
Buggy python submission (verdict: Runtime Error):
import collections as c
# from fractions import gcd
from math import gcd
ip = lambda : map(int, input().split())
# ##############
mod = 1e9+7
S = input()
for i in range(3):
    if S[i] == S[i+1]:
        print('Bad')
        exit()
print('Good')

Fixed submission:
import collections as c
ip = lambda : map(int, input().split())
# ##############
mod = 1e9+7
S = input()
for i in range(3):
    if S[i] == S[i+1]:
        print('Bad')
        exit()
print('Good')
Buggy python submission (verdict: Runtime Error):
import collections as c
# from fractions import gcd
from math import gcd
ip = lambda : map(int, input().split())
# ##############
mod = 1e9+7
n,l = ip()
ans = 0
k=abs(l)
for i in range(l,l+n):
    ans+=i
    if abs(i) < abs(k):
        k = i
ans -= k
print(ans)

Fixed submission:
import collections as c
ip = lambda : map(int, input().split())
# ##############
mod = 1e9+7
n,l = ip()
ans = 0
k=abs(l)
for i in range(l,l+n):
    ans+=i
    if abs(i) < abs(k):
        k = i
ans -= k
print(ans)
Buggy python submission (verdict: Runtime Error):
import collections as c
from math import gcd
ip = lambda : map(int, input().split())
# ##############
mod = 1e9+7
N,M = ip()
a = set()
for i in range(M):
    a.add(int(input()))
dp = [0]*(N+1)
dp[0] = 1
if 1 in a:
    pass
else:
    dp[1] = dp[0]
if N>1:
    for i in range(2,N+1):
        if i in a:
            continue
        dp[i] += dp[i-2] + dp[i-1]
        dp[i] = int(dp[i] % mod)
print(dp[N])

Fixed submission:
import collections as c
ip = lambda : map(int, input().split())
# ##############
mod = 1e9+7
N,M = ip()
a = set()
for i in range(M):
    a.add(int(input()))
dp = [0]*(N+1)
dp[0] = 1
if 1 in a:
    pass
else:
    dp[1] = dp[0]
if N>1:
    for i in range(2,N+1):
        if i in a:
            continue
        dp[i] += dp[i-2] + dp[i-1]
        dp[i] = int(dp[i] % mod)
print(dp[N])
Buggy python submission (verdict: Runtime Error):
import sys
N = int(input())
lis = [int(i) for i in sys.stdin.readline().split()]
x_1,x_2 = 0,0
for i in range(2,N):
    tmp = min(abs(lis[i]-lis[i-1]) + x_1, abs(lis[i] - lis[i-2]) + x_2)
    x_1,x_2 = tmp,x_1
print(tmp)

Fixed submission:
import sys
N = int(input())
lis = [int(i) for i in sys.stdin.readline().split()]
res = [0,abs(lis[1]-lis[0])]
for i in range(2,N):
    tmp = min(abs(lis[i]-lis[i-1]) + res[i-1],abs(lis[i] - lis[i-2]) + res[i-2])
    res.append(tmp)
print(res[-1])
Buggy python submission (verdict: Runtime Error):
N, P = map(int, input().split())
p = P**(1/N)
if p % 1 == 0:
    print(int(p))
    exit()

lim = int(p) + 1

dic = {}

def my(N,newP=P):
    for i in range(2,lim+1):
        while newP % i == 0:
            dic[i] = dic.get(i,0) + 1
            newP = newP // i
        if newP < i or i == lim+1:
            res = 1
            for j,k in dic.items():
                res *= j**(k//N)
            print(res)
            exit()
my(N)
print(1)

Fixed submission:
S = input()
n = 0
for i in S:
    if i == '2':
        n += 1
print(n)
Buggy python submission (verdict: Time Limit Exceeded):
S = input()
n = 0
import re
re.sub('BB+',"BB",S)
re.sub("WW+",'WW',S)


while 'BWBWBW' in S:
    n += 6*S.count('BWBWBW')
    S = S.replace('BWBWBW','WB')
while 'BW' in S:
    n += S.count('BW')
    S = S.replace('BW','WB')
print(n)

Fixed submission:
S = input()
n = 0
k = 0
m = len(S)
for i in range(m):
    if S[i] == 'B':
        n += m - (i+1) -k
        k += 1
print(n)

Buggy python submission (verdict: Time Limit Exceeded):
S = input()
n = 0
import re
re.sub('BB+',"BB",S)
re.sub("WW+",'WW',S)
if 'BWBWBW' in S:
    n += 6*S.count('BWBWBW')
    S = S.replace('BWBWBW','WB')
while 'BW' in S:
    n += S.count('BW')
    S = S.replace('BW','WB')
print(n)

Fixed submission:
S = input()
n = 0
k = 0
m = len(S)
for i in range(m):
    if S[i] == 'B':
        n += m - (i+1) -k
        k += 1
print(n)

Buggy python submission (verdict: Time Limit Exceeded):
S = input()
n = 0
import re
re.sub('BB+',"BB",S)
re.sub("WW+",'WW',S)

while 'BW' in S:
    n += S.count('BW')
    S = S.replace('BW','WB')
print(n)

Fixed submission:
S = input()
n = 0
k = 0
m = len(S)
for i in range(m):
    if S[i] == 'B':
        n += m - (i+1) -k
        k += 1
print(n)

Buggy python submission (verdict: Time Limit Exceeded):
S = input()
n = 0
import re
while 'BW' in S:
    re.sub('BB+',"BB",S)
    re.sub("WW+",'WW',S)
    n += S.count('BW')
    S = S.replace('BW','WB')
print(n)

Fixed submission:
S = input()
n = 0
k = 0
m = len(S)
for i in range(m):
    if S[i] == 'B':
        n += m - (i+1) -k
        k += 1
print(n)

Buggy python submission (verdict: Time Limit Exceeded):
S = input()
n = 0
while 'BW' in S:
    n += S.count('BW')
    S = S.replace('BW','WB')
print(n)

Fixed submission:
S = input()
n = 0
k = 0
m = len(S)
for i in range(m):
    if S[i] == 'B':
        n += m - (i+1) -k
        k += 1
print(n)
Buggy python submission (verdict: Runtime Error):

#組み合わせ、コンビネーション
def cmb(n,r):
  	if n ==1:
      return 0
    else:
      r=min(r,n-r)
      result=1
      for i in range(n-r+1,n+1):
          result*=i
      for i in range(1,r+1):
          result//=i
      return result

#素因数分解、辞書を返す
def factorize(n):
    i=2
    result={}
    while True:
        if i**2>n:
            break
        count=0
        while n%i==0:
            n//=i
            count+= 1
        if count!=0:
            result[i]=count
        i+=1
    if n>1:
        result[n]=1
    return result

N = int(input())
l={}
for i in range(1,N+1):
    for i,j in factorize(i).items():
        l[i] = l.get(i,0)+j


l2 = [0]*5

r = 0
for j,i in l.items():
    if i>=74:
        l2[4]+=1
    elif i>=24:
        l2[3]+=1
    elif i>=14:
        l2[2]+=1
    elif i>=4:
        l2[1]+=1
    elif i>=2:
        l2[0]+=1
# print(l)
# print(l2)

r += l2[4]
r += sum(l2[3:])*(sum(l2)-1)
r += sum(l2[2:])*(sum(l2[1:])-1)
r += cmb(sum(l2[1:]),2)*(sum(l2)-2)
print(r)

Fixed submission:
#組み合わせ、コンビネーション
def cmb(n,r):
    if n==0:return 0
    else:
        r=min(r,n-r)
        result=1
        for i in range(n-r+1,n+1):
            result*=i
        for i in range(1,r+1):
            result//=i
        return result

#素因数分解、辞書を返す
def factorize(n):
    i=2
    result={}
    while True:
        if i**2>n:
            break
        count=0
        while n%i==0:
            n//=i
            count+= 1
        if count!=0:
            result[i]=count
        i+=1
    if n>1:
        result[n]=1
    return result

N = int(input())
l={}
for i in range(1,N+1):
    for i,j in factorize(i).items():
        l[i] = l.get(i,0)+j


l2 = [0]*5

r = 0
for j,i in l.items():
    if i>=74:
        l2[4]+=1
    elif i>=24:
        l2[3]+=1
    elif i>=14:
        l2[2]+=1
    elif i>=4:
        l2[1]+=1
    elif i>=2:
        l2[0]+=1

r += l2[4]
r += sum(l2[3:])*(sum(l2)-1)
r += sum(l2[2:])*(sum(l2[1:])-1)
r += cmb(sum(l2[1:]),2)*(sum(l2)-2)
print(r)
Buggy python submission (verdict: Runtime Error):
N,M=map(int,input().split())
S=input()
T=input()
import math
gcd=int(N*M/math.gcd(N,M))
lis=[int(gcd/N),int(gcd/M)]
for i in range(int(N*M/gcd)):
    if S[int(i*lis[1])]!=T[int(i*lis[0])]:
        print(-1)
        exit()
print(gcd)

Fixed submission:
N,M=map(int,input().split())
S=input()
T=input()
import fractions
gcd=int(N*M/fractions.gcd(N,M))
lis=[int(gcd/N),int(gcd/M)]
for i in range(int(N*M/gcd)):
    if S[int(i*lis[1])]!=T[int(i*lis[0])]:
        print(-1)
        exit()
print(gcd)
Buggy python submission (verdict: Runtime Error):
N=int(input())
lis=[]
for i in range(101):
    for j in range(101):
        lis.append([i,j])
l2=[]
for i in range(N):
    l2.append(list(map(int, input().split())))
for i in lis:
    n=N
    l=0
    for j in l2:
        k=abs(i[0]-j[0])+abs(i[1]-j[1])+j[2]
        if l==k or l==0:
            l=k
            n-=1
            if n==0:
                m=(i[0],i[1],l)
        else: break
    try:
        print('{} {} {}'.format(m[0],m[1],m[2]))
        break
    except NameError:
        continue

Fixed submission:
N=int(input())
if N==1:
    print('Hello World')
else :
    print(int(input())+int(input()))
Buggy python submission (verdict: Runtime Error):
N, M=map(int,input().split())
dic={}
def f(num):
    if not num in dic:
        lis=[]
        for i in range(1,int(num**0.5)+1):
            if num%i==0:
                lis.append(i)
                if i**2!=num:
                    lis.append(num//i)
        lis.sort()
        dic[num]=lis
    return dic[num]

res=0
def c(m,n):
    if n>0:
        for i in f(m):
            j=m//i
            c(j,n-1)
    else:
        global res
        res+=len(f(m))

c(M,n=N-2)
print(res)   

Fixed submission:
def cmb(n,r):
    r=min(r,n-r)
    result=1
    for i in range(n-r+1,n+1):
        result*=i
    for i in range(1,r+1):
        result//=i
    return result

def factorize(n):
    i=2
    result={}
    while True:
        if i**2>n:
            break
        count=0
        while n%i==0:
            n//=i
            count+= 1
        if count!=0:
            result[i]=count
        i+=1
    if n>1:
        result[n]=1
    return result


N,M = map(int,input().split())
l = factorize(M)

r = 1
for i,j in l.items():
    r *= cmb(j+N-1,j)%(10**9+7)
    r %= (10**9+7)
print(r)

Buggy python submission (verdict: Runtime Error):
N, M=map(int,input().split())
def f(num):
    lis=[]
    for i in range(1,int(num**0.5)+1):
        if num%i==0:
            lis.append(i)
            if i**2!=num:
                lis.append(num//i)
    lis.sort()
    return lis

res=0
def c(m,n):
    if n>0:
        print(n,m,f(m))
        for i in f(m):
            j=m//i
            c(j,n-1)
    else:
        global res
        res+=len(f(m))

c(M,n=N-2)
print(res)  

Fixed submission:
def cmb(n,r):
    r=min(r,n-r)
    result=1
    for i in range(n-r+1,n+1):
        result*=i
    for i in range(1,r+1):
        result//=i
    return result

def factorize(n):
    i=2
    result={}
    while True:
        if i**2>n:
            break
        count=0
        while n%i==0:
            n//=i
            count+= 1
        if count!=0:
            result[i]=count
        i+=1
    if n>1:
        result[n]=1
    return result


N,M = map(int,input().split())
l = factorize(M)

r = 1
for i,j in l.items():
    r *= cmb(j+N-1,j)%(10**9+7)
    r %= (10**9+7)
print(r)
Buggy python submission (verdict: Runtime Error):
N,X = map(int, input().split())
def myabs(i):
    return abs(i-X)
xlis = list(map(myabs, map(int, input().split())))

from fractions import gcd

res = xlis[0]
for i in xlis:
    if i%res == 0:
        continue
    res = gcd(i,res)

print(res)

Fixed submission:
A,B = map(int,input().split())
if A%2==1 and B%2==1:
  print('Yes')
else:
  print('No')
Buggy python submission (verdict: Runtime Error):
H,W = map(int,input().split())
lis = ['.' +input()+'.' for _ in range(H)]
lis.insert(0,'.'*W)
lis.append('.'*W)
for i in range(1,H+1):
    for j in range(1,W+1):
        if lis[i][j] == '#':
            if lis[i+1][j]=='#' or lis[i-1][j]=='#' or lis[i][j+1]=='#' or lis[i][j-1] == '#':
                continue
            else:
                print('No')
                exit()
print('Yes')

Fixed submission:
H,W = map(int,input().split())
lis = ['.' +input()+'.' for _ in range(H)]
lis.insert(0,'.'*(W+2))
lis.append('.'*(W+2))
for i in range(1,H+1):
    for j in range(1,W+1):
        if lis[i][j] == '#':
            if lis[i+1][j]=='#' or lis[i-1][j]=='#' or lis[i][j+1]=='#' or lis[i][j-1] == '#':
                continue
            else:
                print('No')
                exit()
print('Yes')
Buggy python submission (verdict: Runtime Error):
n, d = map(int, input().split())
ans = 0
for i in range(n):
    x, y = map(int, input().split())
    if sqrt(x**2 + y**2) <= d:
        ans += 1
print(ans)

Fixed submission:
from math import sqrt
n, d = map(int, input().split())
ans = 0
for i in range(n):
    x, y = map(int, input().split())
    if sqrt(x**2 + y**2) <= d:
        ans += 1
print(ans)
Buggy python submission (verdict: Time Limit Exceeded):
n, m = [int(c) for c in input().split()]
As = [int(c) for c in input().split()]
min_As = min(As)
for i in range(m):
    b, c = [int(c) for c in input().split()]
    if min_As >= c:
        continue
    As += [c] * b
As.sort(reverse=True)
print(sum(As[:n]))

Fixed submission:
n, m = [int(c) for c in input().split()]
A = {}
for a in input().split():
    a = int(a)
    A[a] = A.get(a, 0) + 1
# print(A)

for i in range(m):
    b, c = [int(c) for c in input().split()]
    A[c] = A.get(c, 0) + b
# print(A)

A = sorted([(k, v) for k, v in A.items()], reverse=True)
ans, num = 0, n
for k, v in A:
    # print(k, v, min(num, v))
    ans += k * min(num, v)
    num -= min(num, v)
    if num == 0:
        break
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
n, m = [int(c) for c in input().split()]
As = [int(c) for c in input().split()]
for i in range(m):
    b, c = [int(c) for c in input().split()]
    As += [c] * b
As.sort(reverse=True)
print(sum(As[:n]))

Fixed submission:
n, m = [int(c) for c in input().split()]
A = {}
for a in input().split():
    a = int(a)
    A[a] = A.get(a, 0) + 1
# print(A)

for i in range(m):
    b, c = [int(c) for c in input().split()]
    A[c] = A.get(c, 0) + b
# print(A)

A = sorted([(k, v) for k, v in A.items()], reverse=True)
ans, num = 0, n
for k, v in A:
    # print(k, v, min(num, v))
    ans += k * min(num, v)
    num -= min(num, v)
    if num == 0:
        break
print(ans)
Buggy python submission (verdict: Time Limit Exceeded):
import re
n, q = [int(i) for i in input().split()]
S = input()
for _ in range(q):
    l, r = [int(i) for i in input().split()]
    s = S[l-1:r]
    ans = sum(True for _ in re.finditer('AC', s))
    print(ans)

Fixed submission:
n, q = [int(i) for i in input().split()]
S = input()
counter = [0] * len(S)
for i in range(len(S)):
    if i == 0:
        counter[i] == 0
    elif S[i-1:i+1] == 'AC':
        counter[i] = counter[i-1] + 1
    else:
        counter[i] = counter[i-1]

counter = [0] + counter
# print(counter)


for _ in range(q):
    l, r = [int(i) for i in input().split()]
    print(counter[r] - counter[l])

Buggy python submission (verdict: Time Limit Exceeded):
import re
n, q = [int(i) for i in input().split()]
S = input()
for _ in range(q):
    l, r = [int(i) for i in input().split()]
    s = S[l-1:r]
    ans = sum(True for _ in re.findall('AC', s))
    print(ans)

Fixed submission:
n, q = [int(i) for i in input().split()]
S = input()
counter = [0] * len(S)
for i in range(len(S)):
    if i == 0:
        counter[i] == 0
    elif S[i-1:i+1] == 'AC':
        counter[i] = counter[i-1] + 1
    else:
        counter[i] = counter[i-1]

counter = [0] + counter
# print(counter)


for _ in range(q):
    l, r = [int(i) for i in input().split()]
    print(counter[r] - counter[l])
Buggy python submission (verdict: Time Limit Exceeded):
def f(a, b):
    ans = 0
    for i in range(a, b + 1):
        ans = ans ^ i
    return ans

a, b = [int(i) for i in input().split()]
print(f(a, b))

Fixed submission:
def f(x):
    if x % 4 == 0:
        return x
    elif x % 4 == 1:
        return 1
    elif x % 4 == 2:
        return x + 1
    else:
        return 0

a, b = map(int, input().split())
print(f(a-1) ^ f(b))
Buggy python submission (verdict: Runtime Error):
n, k = [int(i) for i in input().split()]
As = [int(i) for i in input().split()]
def f(x):
    return sum(a^x for a in As)

bs = [f'{a:050b}'[::-1] for a in As]
# print(bs)
ans = ''
strk = f'{k:b}'
# print('strk', strk)
for i in range(len(strk)):
    one = len([True for b in bs if b[i] == '1'])
    zero = len([True for b in bs if b[i] == '0'])
    # print(one, zero)

    if k <= int('1' + ans, 2):
        ans = '0' + ans
        # print('y')
    elif one < zero:
        ans = '1' + ans
    else:
        ans = '0' + ans
    # print('ans', ans)

    # ans = '0' if one > zero else '1'
# ans = ans[::-1]
# print(ans)
# ans = int(ans, 2)
print(f(int(ans, 2)))

Fixed submission:
n, k = [int(i) for i in input().split()]
As = [int(i) for i in input().split()]
def func(x):
    return sum(a^x for a in As)

bs = ['{:050b}'.format(a)[::-1] for a in As]
# print(bs)
strk = '{:b}'.format(k)

ans = ['0'] * len(strk)
# print(strk, ans)
for i in range(len(strk)):
    one = len([True for b in bs if b[len(strk) - 1 - i] == '1'])
    zero = len([True for b in bs if b[len(strk) - 1 - i] == '0'])
    # print(zero, one)

    tmp = ans[:]
    # if k < int('1' + ans, 2):

    # if one == zero:
    #     tmp[i] = '1'
    if zero >= one:
        tmp[i] = '1'
    # else:
    #     ans = ['0' + a for a in ans]
    # print(tmp, int(''.join(tmp), 2))
    if k >= int(''.join(tmp), 2):
        ans = tmp
    # print('ans', ans)

print(func(int(''.join(ans), 2)))

Buggy python submission (verdict: Time Limit Exceeded):
n, k = [int(i) for i in input().split()]
As = [int(i) for i in input().split()]
def f(x):
    return sum(a^x for a in As)

ans = 0
for i in range(k+1):
    ans = max(ans, f(i))
print(ans)


Fixed submission:
n, k = [int(i) for i in input().split()]
As = [int(i) for i in input().split()]
def func(x):
    return sum(a^x for a in As)

bs = ['{:050b}'.format(a)[::-1] for a in As]
# print(bs)
strk = '{:b}'.format(k)

ans = ['0'] * len(strk)
# print(strk, ans)
for i in range(len(strk)):
    one = len([True for b in bs if b[len(strk) - 1 - i] == '1'])
    zero = len([True for b in bs if b[len(strk) - 1 - i] == '0'])
    # print(zero, one)

    tmp = ans[:]
    # if k < int('1' + ans, 2):

    # if one == zero:
    #     tmp[i] = '1'
    if zero >= one:
        tmp[i] = '1'
    # else:
    #     ans = ['0' + a for a in ans]
    # print(tmp, int(''.join(tmp), 2))
    if k >= int(''.join(tmp), 2):
        ans = tmp
    # print('ans', ans)

print(func(int(''.join(ans), 2)))
Buggy python submission (verdict: Runtime Error):
import copy
n, q = [int(i) for i in input().split()]
As = sorted([int(i) for i in input().split()])
for i in range(q):
    x = int(input())
    As_tmp = copy.copy(As)
    As_abs = [abs(a - x) for a in As]
    ans = 0
    # print(As_abs)
    while As_abs:
        ans += As_tmp[-1]
        # print(ans)
        As_tmp.pop(-1)
        As_abs.pop(-1)
        if not As_abs:
            break
        # ans += As[As_abs.index(min(As_abs))]
        idx = As_abs.index(min(As_abs))
        As_tmp.pop(idx)
        As_abs.pop(idx)
        # print(As_abs)
 
    print(ans)

Fixed submission:
n, h, w = int(input()), int(input()), int(input())
print((n-h+1)*(n-w+1))
Buggy python submission (verdict: Runtime Error):
N, As = int(input()), list(map(int, input().split()))
maxA, ans = max(As), 1
while True:
    if pow(ans, maxA) - 1 > N:
        break
    ans += 1
print(ans)

Fixed submission:
ans, w_idx = 0, 0
for i, s in enumerate(input()):
    if s != 'W':
        continue
    ans += i - w_idx
    w_idx += 1
print(ans)
Buggy python submission (verdict: Time Limit Exceeded):
import sys
def input(): return sys.stdin.readline().strip()

N, As = int(input()), list(map(int, input().split()))
As = [As[i] - i - 1 for i in range(N)]
ans = sys.maxsize
for b in range(min(As), max(As) + 1):
    ans = min(ans, sum(map(lambda A: abs(A - b), As)))
print(ans)

Fixed submission:
N, As = int(input()), map(int, input().split())
As = sorted([A - i - 1 for i, A in enumerate(As)])
b = As[N // 2]
print(sum(map(lambda A: abs(A - b), As)))

Buggy python submission (verdict: Runtime Error):
N, As = int(input()), list(map(int, input().split()))
As = [As[i] - i - 1 for i in range(N)]
ans = sys.maxsize
for b in range(min(As), max(As) + 1):
    ans = min(ans, sum(map(lambda A: abs(A - b), As)))
print(ans)

Fixed submission:
N, As = int(input()), map(int, input().split())
As = sorted([A - i - 1 for i, A in enumerate(As)])
b = As[N // 2]
print(sum(map(lambda A: abs(A - b), As)))
Buggy python submission (verdict: Runtime Error):
s = input()
ch = [chr(i) for i in range(97, 97+26)]
for i in range(len(ch)):
    if not ch[i] in s :
        print(ch[i])
        sys.exit()
print("None")

Fixed submission:
s = input()
ch = {chr(i) for i in range(ord('a'), ord('z')+1)}
ss = set()
for i in range(len(s)): ss.add(s[i])
tmp = sorted(list(ch ^ ss))
print(tmp[0] if len(tmp) else "None")

Buggy python submission (verdict: Runtime Error):
s = input()
ch = [chr(i) for i in range(ord('a'), ord('z')+1)]
for i in range(len(ch)):
    if not ch[i] in s :
        print(ch[i])
        sys.exit()
print("None")

Fixed submission:
s = input()
ch = {chr(i) for i in range(ord('a'), ord('z')+1)}
ss = set()
for i in range(len(s)): ss.add(s[i])
tmp = sorted(list(ch ^ ss))
print(tmp[0] if len(tmp) else "None")

Buggy python submission (verdict: Runtime Error):
ch = [chr(i) for i in range(ord('a'), ord('z')+1)]
s = input()
for ss in ch:
    if not ss in s:
        print(ss)
        sys.exit()
print("None")

Fixed submission:
s = input()
ch = {chr(i) for i in range(ord('a'), ord('z')+1)}
ss = set()
for i in range(len(s)): ss.add(s[i])
tmp = sorted(list(ch ^ ss))
print(tmp[0] if len(tmp) else "None")

Buggy python submission (verdict: Runtime Error):
s = input()
ch = {chr(i) for i in range(ord('a'), ord('z')+1)}
for i in range(len(s)): ch.remove(s[i])
tmp = sorted(list(ch))
print(tmp[0] if len(tmp) else "None")

Fixed submission:
s = input()
ch = {chr(i) for i in range(ord('a'), ord('z')+1)}
ss = set()
for i in range(len(s)): ss.add(s[i])
tmp = sorted(list(ch ^ ss))
print(tmp[0] if len(tmp) else "None")
Buggy python submission (verdict: Time Limit Exceeded):
import sys
line = sys.stdin.readline

n = int(line())
a = list(map(int, line().split()))
l = [0 for i in range(max(a)+1)]
for i in a: l[i] += 1
l.reverse()
h = 0
for i in range(len(l)):
    if l[i] > 4:
        print(l[i])
        sys.exit()
    if l[i] >= 2 and h:
        print((len(l) - 1 - i) * h)
        sys.exit()
    if l[i] >= 2:
        h = len(l) - 1 - i
print(0)

Fixed submission:
import sys
line = sys.stdin.readline

n = int(line())
a = list(map(int, line().split()))
a.sort(reverse=True)
summ = 0
h = 0
for i in range(len(a)):
    summ += 1
    if i and a[i] != a[i-1]:
        summ = 1
    if summ == 2:
        if h:
            print(a[i] * h)
            sys.exit()
        else:
            h = a[i]
    if summ == 4:
        print(a[i] * a[i])
        sys.exit()
print(0)