常见js排序算法（冒泡，快速，选择，插入）

    console.log("冒泡");
    var arr = [1,24,4,2,67,2124,43,2]
    var bubbleSort = function(arr){
        if(arr.length <= 1){
            return arr
        }
        var temp;
        for(var i = 0; i < arr.length-1 ;i++){
            for(var j = i+1; j<arr.length; j++){
                if(arr[i] > arr[j]){
                    temp = arr[i];
                    arr[i] = arr[j];
                    arr[j] = temp;
                }
            }
        }
        return console.log(arr);
    }
    bubbleSort(arr);
    
    console.log("快速")
    var quickSort = function(arr){
        if(arr.length <= 1){
            return arr
        };
        var left = [];
        var right = [];
        var pointIndex = Math.floor(arr.length/2);
        var point = arr.splice(pointIndex,1)[0];
        for (var i = 0; i < arr.length; i++) {
            if (arr[i] < point) {
                left.push(arr[i])
            }else {
                right.push(arr[i])
            }
        }
        return quickSort(left).concat([point],quickSort(right));
        
    }
    console.log(quickSort(arr))
    
    console.log("选择")
    var selectSort = function(arr){
        var index, min, temp;
        for (var i = 0; i < arr.length; i++) {
            index = i;
            min = arr[i];
            for (var j = i + 1; j < arr.length; j++) {
                if (arr[j] < min){
                    index = j;
                }
            }
            if(index != i){
                temp = arr[i];
                arr[i] = arr[index];
                arr[index] = temp;  
            }
        }
        return arr
    }
    console.log(selectSort([1,24,4,2,67,2124,43,2]));
    
    console.log("插入排序");
    var insert = function(arr){
        var index,insert;
        for(var i = 0; i<arr.length-1 ;i++){
            index = i + 1;
            insert = arr[i+1];
            for(var j = i; j >= 0 ;j--){
                if(arr[j] > insert){
                    arr[j+1] = arr[j]
                    index = j;
                }
            }
            arr[index] = insert;
        }
        return arr
    }
    console.log(insert([1,24,4,2,67,2124,43,2]))