Shuffle an array using the Pencil-and-paper method I made it 12 bytes smaller by using a for/in loop
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Fisher–Yates shuffle
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| 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. | |
| } |
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| 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) |
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| 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. |
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| <!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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