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Fisher–Yates shuffle

Fork of the awesome Fisher–Yates shuffle by tsaniel

Shuffle an array using the Pencil-and-paper method I made it 12 bytes smaller by using a for/in loop

function(
a, // an array
b // placeholder
){
for(b in a)a.push(a.splice(Math.random()*b,1))
//take out a random piece of the array and append it to the end.
//this works because the splice method returns the piece it removes.
}
function(a,b){for(b=a.length;b;)a.push(a.splice(Math.random()*b--,1)[0])}
function(a,b){for(b in a)a.push(a.splice(Math.random()*b,1));return a}
function(a,b){for(b in a)a.push(a.splice(Math.random()*b,1))}
function(a){a.sort(function(){return .5-Math.random()})}
//legend:
//1. the original
//2. the fork with return (the original function doesn't return a, I think it should)
//3. the fork without return (less practical, but it's smaller)
//4. other method that is slightly smaller (not the same method as the original)
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
Version 2, December 2004
Copyright (C) 2011 YOUR_NAME_HERE <YOUR_URL_HERE>
Everyone is permitted to copy and distribute verbatim or modified
copies of this license document, and changing it is allowed as long
as the name is changed.
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. You just DO WHAT THE FUCK YOU WANT TO.
<!DOCTYPE html>
<title>Foo</title>
<div>Expected value: <b>Random numbers</b></div>
<div>Actual value: <b id="ret"></b></div>
<script>
// write a small example that shows off the API for your example
// and tests it in one fell swoop.
var myFunction = function(a,b){for(b in a)a.push(a.splice(Math.random()*b,1))}
var a = [1,2,3,4,5,6,7,8,9];
myFunction(a);
document.getElementById( "ret" ).innerHTML = a
</script>
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