python - 从python列表中选择一些项目: please explain me why this is not working

Question

import random
numbers = [0,1,2,3,4,5,6,7,8,9]
random.shuffle(numbers)
def sayi(s):
    s[0:4]
    return s

print sayi(numbers)

我想选择列表中的前 4 项来创建 4 位数字。但我做不到。请帮助我。

Answer 1

import random
numbers = [0,1,2,3,4,5,6,7,8,9]
random.shuffle(numbers)
def sayi(s):
    return s[0:4]

print sayi(numbers)

您应该返回切片数组，但您正在返回整个数组。切片不会修改原始数组中的项目，它会创建新数组。