def main():
    import sys
    input = sys.stdin.readline

    mod = 10**12
    ans = 1
    N = int(input())
    flg = 0
    for i in range(1, N+1):
        ans = ans * i
        if ans >= mod:
            flg = 1
            ans %= mod
        if ans == 0:
            print('0' * 12)
            exit()
    if flg:
        print(str(ans).zfill(12))
    else:
        print(ans)


if __name__ == '__main__':
    main()