Buggy python submission (verdict: Runtime Error):
import sys
from bisect import bisect
from itertools import accumulate

def main():
    input = sys.stdin.readline
    N = int(input())
    A = sorted(list(map(int, input().split())))
    B = sorted(list(map(int, input().split())))
    C = sorted(list(map(int, input().split())))

    Bn = [0] * N
    for i in range(N):
        b = B[i]
        m = bisect(C, b)
        Bn[i] = (N - m)

    Bn = list(accumulate(Bn[::-1]))[::-1]

    ans = 0
    for i in range(N):
        a = A[i]
        m = bisect(B, a)
        ans += Bn[m]

    print(ans)


if __name__ == '__main__':
    main()


Fixed submission:
import sys
from bisect import bisect
from itertools import accumulate

def main():
    input = sys.stdin.readline
    N = int(input())
    A = sorted(list(map(int, input().split())))
    B = sorted(list(map(int, input().split())))
    C = sorted(list(map(int, input().split())))

    Bn = [0] * N
    for i in range(N):
        b = B[i]
        m = bisect(C, b)
        Bn[i] = (N - m)

    Bn = list(accumulate(Bn[::-1]))[::-1]
    Bn += [0]

    ans = 0
    for i in range(N):
        a = A[i]
        m = bisect(B, a)
        ans += Bn[m]

    print(ans)


if __name__ == '__main__':
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from bisect import bisect

def main():
    input = sys.stdin.readline
    N = int(input())
    A = sorted(list(map(int, input().split())))
    B = sorted(list(map(int, input().split())))
    C = sorted(list(map(int, input().split())))

    Bn = [0] * N
    for i in range(N):
        b = B[i]
        m = bisect(C, b)
        Bn[i] = (N - m)

    ans = 0
    for i in range(N):
        a = A[i]
        m = bisect(B, a)
        ans += sum(Bn[m:])

    print(ans)


if __name__ == '__main__':
    main()


Fixed submission:
import sys
from bisect import bisect
from itertools import accumulate

def main():
    input = sys.stdin.readline
    N = int(input())
    A = sorted(list(map(int, input().split())))
    B = sorted(list(map(int, input().split())))
    C = sorted(list(map(int, input().split())))

    Bn = [0] * N
    for i in range(N):
        b = B[i]
        m = bisect(C, b)
        Bn[i] = (N - m)

    Bn = list(accumulate(Bn[::-1]))[::-1]
    Bn += [0]

    ans = 0
    for i in range(N):
        a = A[i]
        m = bisect(B, a)
        ans += Bn[m]

    print(ans)


if __name__ == '__main__':
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from bisect import bisect

def main():
    input = sys.stdin.readline
    N = int(input())
    A = sorted(list(map(int, input().split())))
    B = sorted(list(map(int, input().split())))
    C = sorted(list(map(int, input().split())))

    ans = 0
    for a in A:
        n = bisect(B, a)
        for b in B[n:]:
            m = bisect(C, b)
            ans += (N - m)

    print(ans)



if __name__ == '__main__':
    main()


Fixed submission:
import sys
from bisect import bisect
from itertools import accumulate

def main():
    input = sys.stdin.readline
    N = int(input())
    A = sorted(list(map(int, input().split())))
    B = sorted(list(map(int, input().split())))
    C = sorted(list(map(int, input().split())))

    Bn = [0] * N
    for i in range(N):
        b = B[i]
        m = bisect(C, b)
        Bn[i] = (N - m)

    Bn = list(accumulate(Bn[::-1]))[::-1]
    Bn += [0]

    ans = 0
    for i in range(N):
        a = A[i]
        m = bisect(B, a)
        ans += Bn[m]

    print(ans)


if __name__ == '__main__':
    main()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from bisect import bisect

def main():
    input = sys.stdin.readline
    N = int(input())
    A = list(map(int, input().split()))
    B = list(map(int, input().split()))
    C = list(map(int, input().split()))

    ans = 0
    for a in A:
        for b in B:
            for c in C:
                if a < b < c:
                    ans += 1

    print(ans)



if __name__ == '__main__':
    main()


Fixed submission:
import sys
from bisect import bisect
from itertools import accumulate

def main():
    input = sys.stdin.readline
    N = int(input())
    A = sorted(list(map(int, input().split())))
    B = sorted(list(map(int, input().split())))
    C = sorted(list(map(int, input().split())))

    Bn = [0] * N
    for i in range(N):
        b = B[i]
        m = bisect(C, b)
        Bn[i] = (N - m)

    Bn = list(accumulate(Bn[::-1]))[::-1]
    Bn += [0]

    ans = 0
    for i in range(N):
        a = A[i]
        m = bisect(B, a)
        ans += Bn[m]

    print(ans)


if __name__ == '__main__':
    main()