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;
 })()