def factorial(x):
    if x == 0:
        return 1
    return x * factorial(x-1)

def solve(n):
    ret = factorial(min(100, n))
    mod = 1000000000000
    if ret < mod:
        return ret
    return "{:012d}".format(ret % mod)

def main():
    n = int(input())
    print(solve(n))

if __name__ == '__main__':
    main()