Check if two arrays have the same contents (in any order)

ruby arrays comparison
Taymon picture Taymon · Jun 6, 2012 · Viewed 77.4k times · Source

I'm using Ruby 1.8.6 with Rails 1.2.3, and need to determine whether two arrays have the same elements, regardless of whether or not they're in the same order. One of the arrays is guaranteed not to contain duplicates (the other might, in which case the answer is no).

My first thought was

require 'set'
a.to_set == b.to_set

but I was wondering if there was a more efficient or idiomatic way of doing it.

Answer

Mori picture Mori · Jun 6, 2012

This doesn't require conversion to set:

a.sort == b.sort

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