Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [list(map(int,input().split())) for _ in range(N)]
    MOD = 10**9+7
    
    dp = [[0 for _ in range((1<<N)+1)] for _ in range(N+1)]
    dp[0][0] = 1

    for i in range(N):
        for s in range(1<<N):
            if dp[i][s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    dp[i+1][s|jb] += dp[i][s]
    
    print(dp[-1][(1<<N)-1]%MOD)

if __name__ == "__main__":
    main()


Fixed submission:
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [list(map(int,input().split())) for _ in range(N)]
    MOD = 10**9+7
    
    dp = [1] + [0 for _ in range(1<<N)]

    for i in range(N):
        use = [0 for _ in range((1<<N)+1)]
        for s in range(1<<N):
            if dp[s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    use[s^jb] += dp[s]
        dp = use
    
    print(dp[(1<<N)-1]%MOD)

if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
N = int(input())
a = [[int(_) for _ in input().split()] for _ in range(N)]
MOD = 10**9+7

dp = [[0 for _ in range((1<<N)+1)] for _ in range(N+1)]
dp[0][0] = 1

for i in range(N):
    for s in range(1<<N):
        if dp[i][s] == 0:continue
        for j in range(N):
            jb = 1<<j
            if not (s&jb) and a[i][j]:
                dp[i+1][s|jb] += dp[i][s]
    
print(dp[N][(1<<N)-1]%MOD)


Fixed submission:
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [list(map(int,input().split())) for _ in range(N)]
    MOD = 10**9+7
    
    dp = [1] + [0 for _ in range(1<<N)]

    for i in range(N):
        use = [0 for _ in range((1<<N)+1)]
        for s in range(1<<N):
            if dp[s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    use[s^jb] += dp[s]
        dp = use
    
    print(dp[(1<<N)-1]%MOD)

if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
N = int(input())
a = [[int(_) for _ in input().split()] for _ in range(N)]
MOD = 10**9+7

dp = [[0 for _ in range((1<<N)+1)] for _ in range(N+1)]
dp[0][0] = 1

for i in range(N):
    for s in range(1<<N):
        if dp[i][s] == 0:
            continue
        for j in range(N):
            jb = 1<<j
            if not (s&jb) and a[i][j]:
                dp[i+1][s|jb] += dp[i][s]
    
print(dp[-1][(1<<N)-1]%MOD)


Fixed submission:
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [list(map(int,input().split())) for _ in range(N)]
    MOD = 10**9+7
    
    dp = [1] + [0 for _ in range(1<<N)]

    for i in range(N):
        use = [0 for _ in range((1<<N)+1)]
        for s in range(1<<N):
            if dp[s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    use[s^jb] += dp[s]
        dp = use
    
    print(dp[(1<<N)-1]%MOD)

if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
N = int(input())
a = [[int(_) for _ in input().split()] for _ in range(N)]
MOD = 10**9+7

dp = [[0 for _ in range((1<<N)+1)] for _ in range(N+1)]
dp[0][0] = 1

for i in range(N):
    use = [0 for _ in range((1<<N)+1)]
    for s in range(1<<N):
        if dp[i][s] == 0:
            continue
        for j in range(N):
            jb = 1<<j
            if not (s&jb) and a[i][j]:
                dp[i+1][s|jb] += dp[i][s]
    
print(dp[-1][(1<<N)-1]%MOD)


Fixed submission:
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [list(map(int,input().split())) for _ in range(N)]
    MOD = 10**9+7
    
    dp = [1] + [0 for _ in range(1<<N)]

    for i in range(N):
        use = [0 for _ in range((1<<N)+1)]
        for s in range(1<<N):
            if dp[s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    use[s^jb] += dp[s]
        dp = use
    
    print(dp[(1<<N)-1]%MOD)

if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [[int(_) for _ in input().split()] for _ in range(N)]
    MOD = 10**9+7
    
    dp = [[0 for _ in range((1<<N)+1)] for _ in range(N+1)]
    dp[0][0] = 1

    for i in range(N):
        use = [0 for _ in range((1<<N)+1)]
        for s in range(1<<N):
            if dp[i][s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    dp[i+1][s|jb] += dp[i][s]
    
    print(dp[-1][(1<<N)-1]%MOD)

if __name__ == "__main__":
    main()


Fixed submission:
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [list(map(int,input().split())) for _ in range(N)]
    MOD = 10**9+7
    
    dp = [1] + [0 for _ in range(1<<N)]

    for i in range(N):
        use = [0 for _ in range((1<<N)+1)]
        for s in range(1<<N):
            if dp[s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    use[s^jb] += dp[s]
        dp = use
    
    print(dp[(1<<N)-1]%MOD)

if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [list(map(int,input().split())) for _ in range(N)]
    MOD = 10**9+7
    
    dp = [[0 for _ in range((1<<N)+1)] for _ in range(N+1)]
    dp[0][0] = 1

    for i in range(N):
        use = [0 for _ in range((1<<N)+1)]
        for s in range(1<<N):
            if dp[i][s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    dp[i+1][s|jb] += dp[i][s]
    
    print(dp[-1][(1<<N)-1]%MOD)

if __name__ == "__main__":
    main()


Fixed submission:
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [list(map(int,input().split())) for _ in range(N)]
    MOD = 10**9+7
    
    dp = [1] + [0 for _ in range(1<<N)]

    for i in range(N):
        use = [0 for _ in range((1<<N)+1)]
        for s in range(1<<N):
            if dp[s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    use[s^jb] += dp[s]
        dp = use
    
    print(dp[(1<<N)-1]%MOD)

if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [list(map(int,input().split())) for _ in range(N)]
    MOD = 10**9+7
    
    dp = [1] + [0 for _ in range(1<<N)]

    for i in range(N):
        use = [0 for _ in range((1<<N)+1)]
        for s in range(1<<N):
            if dp[s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    use[s^jb] += dp[s]
                    use[s^jb] %= MOD
        dp = use
    
    print(dp[(1<<N)-1])
        
if __name__ == "__main__":
    main()


Fixed submission:
import sys
input = sys.stdin.buffer.readline

def main():
    N = int(input())
    a = [list(map(int,input().split())) for _ in range(N)]
    MOD = 10**9+7
    
    dp = [1] + [0 for _ in range(1<<N)]

    for i in range(N):
        use = [0 for _ in range((1<<N)+1)]
        for s in range(1<<N):
            if dp[s] == 0:
                continue
            for j in range(N):
                jb = 1<<j
                if not (s&jb) and a[i][j]:
                    use[s^jb] += dp[s]
        dp = use
    
    print(dp[(1<<N)-1]%MOD)

if __name__ == "__main__":
    main()