From: Harry Kakueki <list.push@...>
Date: 2008-05-11T08:39:54+09:00
Subject: Re: Delete every other value in an array

>
> Here is one way.
>
> arr = %w[a b c d e f g h i j k]
> p arr.select{|x| arr.index(x) % 2 == 0}
>
> Harry
>
>

Oops. My code has a bug. It can fall down when there are duplicates.
Try this.

arr = %w[a b c d b f g h i j k l m]

p arr.select{|x| arr.index(x) % 2 == 0}#> ["a", "c", "g", "i", "k", "m"]

res = []
(0...arr.length).step(2) {|x| res << arr[x]}
p res #> ["a", "c", "b", "g", "i", "k", "m"]

Harry
-- 
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