js 冒泡排序

var arr = [9,1,2,5,4,6,5,8];
    function sort_arr (arr){
        var temp ,_arr = arr,count =  _arr.length;
        for(var i=0;i< count;i++){
            for(var j=i+1; j<count;j++){
                if(_arr[i]>_arr[j]){
                    temp=_arr[i];
                    _arr[i] = _arr[j];
                    _arr[j] =temp;
                }
            }
        }
        return arr;
    }
    alert(sort_arr(arr));