如何使用切片反转列表？

Question

假设我有一个字符串text ="Hello".我想分别打印字符串的奇数/偶数位置.我已设法按正常顺序执行此操作(请参阅下面的代码).

现在的问题是我想做同样但从最后开始.也就是说,奇数现在等于"le",甚至等于"olH".

    text = "Hello"

    # Normal order
    odd = text[1::2] # --> "el"
    even = text[0::2] # --> "Hlo"

    # Reverse order (WRONG)
    odd = text[-2::2] 
    even = text[-1::2]

Answer 1

你还需要否定增量:

oddReverse = text[-2::-2]
evenReverse = text[-1::-2]