n=int(input())
sum=1
mod=10**12
if 50<=n:
    print("0"*12)
else:
    for i in range(1,n+1):
        sum*=i
    if 10**11<=sum:
        if n==20:
            print("00"+str(sum%mod))
        elif n==32:
            print("0"+str(sum%mod))
        else:
            print(sum%mod)
    else:
        print(sum)