1、手写
def Foo(x):
if (x==1):
return 1
else:
return x*Foo(x-1)
print(Foo(4))
2、系统库函数
math.factorial(4)
3、for循环
def foo(n):
result = 1
for i in range(1,n+1):
if i == 1:
result = 1
else:
result = i * result
return result
foo(4)
标签：foo,return,else,result,阶乘,Foo From： https://www.cnblogs.com/z977690557/p/16661717.html