js 随机数

Posted 2020-08-14

function shuffle(arr){
    var len = arr.length;
    for(var i = 0;i<len -1;i++)
    {
        var idx = Math.floor(Math.random() * (len - 1));
        var temp = arr[idx];
        arr[idx] = arr[len - i - 1];
        arr[len - i - 1] = temp;
    }
    return arr;
}