Fisher-Yates shuffle algorithm with Ruby

The simplest shuffle algorithm, Fisher-Yates, is widely used and easy to implement. I personally used it to create a card game in Sinatra:

# Fisher-Yates Shuffle Algorithm module FisherYates def self.shuffle(numbers) n = numbers.length while n > 0 x = rand(n-=1) numbers[x], numbers[n] = numbers[n], numbers[x] end return numbers end end 

So let's imagine you want to use it in your Rails app, you could do something like this:

 def initialize(numbers) shuffle = FisherYates.shuffle(numbers) return shuffle.inspect end 

If you want to test this script from shell, add this after FisherYates, and save as shuffle.rb. Add numbers as arguments, or just execute script to shuffle defined numbers from array:

 @numbers = [1,2,3,4,5,6,7,8,9,10,12,13,14] if ARGV.empty? puts FisherYates.shuffle(@numbers).inspect else puts FisherYates.shuffle(ARGV).inspect end 

Without inspect you would get each number in separated line, but with inspect we receive array of numbers printed in terminal.