[JS] shuffle

function shuffle(arr) {
    var i = arr.length; 
    var random; 
    var temp;

    while (i > 0) {
        random = Math.floor(Math.random() * i--);

        temp = arr[i];
        arr[i] = arr[random];
        arr[random] = temp;
    }

    return arr;
}

[출처] https://gist.github.com/seunggabi/d018657da5b15a4b50ce1693d12446c0