N = int(input())
ANS = 1
MOD = 10**12
OVER = False
for i in range(1,N+1):
    ANS *= i
    if ANS % MOD == 0:
        print('000000000000')
        exit()
    if ANS//MOD>0:
       OVER = True
    ANS = ANS % MOD
if OVER:
    print(str(ANS).zfill(12))
else:
    print(ANS)