function quickSort(arr){    if(arr.length<=1){        return arr;    }        var num = Math.floor(arr.length/2);        var numValue = http://www.mamicode.com/arr.splice(num,1);        var left = [];    var right = [];        for(var i=0;i<arr.length;i++){        if(arr[i]<numValue){            left.push(arr[i]);        }        else{            right.push(arr[i]);        }    }        return quickSort(left).concat([numValue],quickSort(right));}alert(quickSort([12,5,37,6,22,40]));