版权声明: https://blog.csdn.net/dangzhangjing97/article/details/88826052
def fun(n):
if n<=1:
return 1
else:
return n*fun(n-1)
num=fun(int(raw_input()))
print num
def fun(n):
if n<=1:
return 1
else:
return n*fun(n-1)
num=fun(int(raw_input()))
print num