javascript算法

代码运行环境： nodejs + mochajs

/*
 *选择排序
 *每次查找数组最小数据
 *将最小数据排到左侧   
 */
var assert = require('assert');
describe('Array', function() {
  describe('#indexOf()', function() {

    var result = [1, 1, 2, 3, 55, 90]

    it('quickSortTest', function() {
        var arr1 = [3, 2, 55, 1, 90, 1]
        assert.equal(result.toString(), coolSort.quickSort(arr1).toString());
    });

    it('bubbleSortTest', function() {
        var arr2 = [1, 3, 2, 55, 90, 1]

        assert.equal(result.toString(), coolSort.selectionsSort(arr2).toString());        
    })

    it('selectionsSortTest', function() {
        var arr3 = [1, 55, 2, 3, 90, 1]

        assert.equal(result.toString(), coolSort.selectionsSort(arr3).toString());        
    })
  });
});

var coolSort = (function() {

    function compare(arg1, arg2) {
        if(arg1 > arg2) {
            return 1;
        } else if(arg1 === arg2) {
            return 0;
        } else {
            return -1;
        }
    }

    function swap(arr, arg1, arg2) {
        var temp = arr[arg1];
        arr[arg1] = arr[arg2];
        arr[arg2] = temp;
    }

    this.selectionsSort = function(arr) {
        "use strict";
        //判断是否是数组
        if(Object.prototype.toString.call(arr) !== "[object Array]") return arr;

        var len = arr.length,
            min = 0,
            j = 0,
            temp = 0;

        //判断数组长度
        if(len <= 1) return arr;


        for(var i = 0; i < len -1; i++) {

            min = i;
            //查找出最小的一个数据
            for(j = i + 1; j < len; j++) {
                if(compare(arr[min], arr[j]) === 1)
                    min = j;
            }
            //如果i不是最小的数据，将i与最小数据进行交换
            if(min !== i) swap(arr, min, i)

        }

        return arr;        
    }

    this.quickSort = function(arr) {
        "use strict";
        if(arr.length <= 1) return arr;

        var pivotIndex = Math.floor((arr.length / 2));
        var pivot = arr.splice(pivotIndex, 1);

        var left = [];
        var right = [];

        for(var i =0; i < arr.length; i++) {
            if(arr[i] < pivot) {
                left.push(arr[i]);
            } else {
                right.push(arr[i]);
            }
        }

        return quickSort(left).concat(pivot, quickSort(right))
    }

    this.bubbleSort = function (arr) {
        "use strict";
        var temp = 0,
            len = arr.length,
            j = 0;
        for(var i =0; i < len - 1; i++) {
            for(j = 0; j < len - i - 1; j++) {
                if(compare(arr[j], arr[j + 1]) === 1 ) {
                    swap(arr, j , j + 1);
                }
            }
        }
        return arr;
    }

    return this;
})()