-- coding: utf-8 --

from functools import reduce

def prod(L): def C(a,b): return a*b reduce(C,L)

L=[3,5,7,9] print ('357*9=',prod(L))

为什么函数输出的是None啊，编程小白一枚求教

#2 Created at ... [Delete] [Delete and Lock User]

reduce前面缺少 return 自定义 prod(L)函数缺少返回值所以输出None

#3 Created at ... [Delete] [Delete and Lock User]

from functools import reduce

def prod(L): def C(a,b): return a*b return reduce(C,L)

L=[3,5,7,9] print ('357*9=',prod(L))

**函数C有返回值，但是prod没有返回值。

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#4 Created at ... [Delete] [Delete and Lock User]

理解了，谢谢！