# https://yukicoder.me/problems/no/500

def main(n):
    MAX = 1000000000000
    res = 1
    for i in range(1, n+1):
        res = res * i
    if res > MAX:
        res %= MAX
    print("{:012}".format(res))

if __name__ == "__main__":
    n = int(input())
    main(n)