冒泡算法排序

for(var i = 0;i<arr.length;i++){
    for(var j = 0;j<arr.length-i;j++){
        if(arr[j] > arr[j+1]){ //
            var temp = arr[j];
            arr[j] = arr[j+1];
            arr[j+1] = temp;
        }
    }
}