N = int(input())
ans=1
for i in range(1, N+1):
    ans*=i
    if ans%(10**12)==0:
        break
if ans==0:
    print("0"*12)
else:
    if ans>=10**12:
        print("0"*(12-len(str(ans%(10**12)))), end="")
    print(ans%(10**12))