sort.js

(function (factory) {
    if (typeof module !== 'undefined' && typeof exports === 'object' && define.cmd) {
        module.exports = factory();
    } else if (typeof define === 'function' && define.amd) {
        define([], factory);
    } else {
        window.Sort = factory()
    }
})(function () {

    function merge(left, right) {
        var result = [];
     
        while (left.length>0 && right.length>0) {
            if (left[0] <= right[0]) {
                result.push(left.shift());
            } else {
                result.push(right.shift());
            }
        }
     
        while (left.length)
            result.push(left.shift());
     
        while (right.length)
            result.push(right.shift());
     
        return result;
    }

    function partition (arr, left ,right) {     //分区操作
        var pivot = left,                      //设定基准值（pivot）
            index = pivot + 1;
        for (var i = index; i <= right; i++) {
            if (arr[i] < arr[pivot]) {
                swap(arr, i, index);
                index++;
            }       
        }
        swap(arr, pivot, index - 1);
        return index-1;
    }
     
    function swap (arr, i, j) {
        var temp = arr[i];
        arr[i] = arr[j];
        arr[j] = temp;
    }

    var len;    //因为声明的多个函数都需要数据长度，所以把len设置成为全局变量

    var counter = [];
    
   function buildMaxHeap(arr) {   //建立大顶堆
       len = arr.length;
       for (var i = Math.floor(len/2); i >= 0; i--) {
           heapify(arr, i);
       }
   }
    
   function heapify(arr, i) {     //堆调整
       var left = 2 * i + 1,
           right = 2 * i + 2,
           largest = i;
    
       if (left < len && arr[left] > arr[largest]) {
           largest = left;
       }
    
       if (right < len && arr[right] > arr[largest]) {
           largest = right;
       }
    
       if (largest != i) {
           swap(arr, i, largest);
           heapify(arr, largest);
       }
   }
    
    return {

        /**
         * 冒泡排序
         */
        bubbleSort: function (arr) {
            var len = arr.length;
            for (var i = 0; i < len; i++) {
                for (var j = 0; j < len - 1 - i; j++) {
                    if (arr[j] > arr[j + 1]) {        //相邻元素两两对比
                        var temp = arr[j + 1];        //元素交换
                        arr[j + 1] = arr[j];
                        arr[j] = temp;
                    }
                }
            }
            return arr;
        },

        /**
         * 选择排序
         */
        selectionSort: function (arr) {
            var len = arr.length;
            var minIndex, temp;
            for (var i = 0; i < len - 1; i++) {
                minIndex = i;
                for (var j = i + 1; j < len; j++) {
                    if (arr[j] < arr[minIndex]) {     //寻找最小的数
                        minIndex = j;                 //将最小数的索引保存
                    }
                }
                temp = arr[i];
                arr[i] = arr[minIndex];
                arr[minIndex] = temp;
            }
            return arr;
        },

        /**
         * 插入排序
         */
        insertionSort:function(arr) {
            var len = arr.length;
            var preIndex, current;
            for (var i = 1; i < len; i++) {
                preIndex = i - 1;
                current = arr[i];
                while(preIndex >= 0 && arr[preIndex] > current) {
                    arr[preIndex+1] = arr[preIndex];
                    preIndex--;
                }
                arr[preIndex+1] = current;
            }
            return arr;
        },

        shellSort:function(arr) {
            var len = arr.length,
                temp,
                gap = 1;
            while(gap < len/3) {          //动态定义间隔序列
                gap =gap*3+1;
            }
            for (gap; gap> 0; gap = Math.floor(gap/3)) {
                for (var i = gap; i < len; i++) {
                    temp = arr[i];
                    for (var j = i-gap; j > 0 && arr[j]> temp; j-=gap) {
                        arr[j+gap] = arr[j];
                    }
                    arr[j+gap] = temp;
                }
            }
            return arr;
        },

        mergeSort:function(arr) {  //采用自上而下的递归方法
            var len = arr.length;
            if(len < 2) {
                return arr;
            }
            var middle = Math.floor(len / 2),
                left = arr.slice(0, middle),
                right = arr.slice(middle);
            return merge(mergeSort(left), mergeSort(right));
        },

        quickSort:function(arr, left, right) {
            var len = arr.length,
                partitionIndex,
                left = typeof left != 'number' ? 0 : left,
                right = typeof right != 'number' ? len - 1 : right;
         
            if (left < right) {
                partitionIndex = partition(arr, left, right);
                quickSort(arr, left, partitionIndex-1);
                quickSort(arr, partitionIndex+1, right);
            }
            return arr;
        },

        heapSort:function(arr) {
            buildMaxHeap(arr);
         
            for (var i = arr.length-1; i > 0; i--) {
                swap(arr, 0, i);
                len--;
                heapify(arr, 0);
            }
            return arr;
        },

        countingSort:function(arr, maxValue) {
            var bucket = new Array(maxValue+1),
                sortedIndex = 0;
                arrLen = arr.length,
                bucketLen = maxValue + 1;
         
            for (var i = 0; i < arrLen; i++) {
                if (!bucket[arr[i]]) {
                    bucket[arr[i]] = 0;
                }
                bucket[arr[i]]++;
            }
         
            for (var j = 0; j < bucketLen; j++) {
                while(bucket[j] > 0) {
                    arr[sortedIndex++] = j;
                    bucket[j]--;
                }
            }
         
            return arr;
        },

        /**
         * 
         * @param {*} arr 
         * @param {*} bucketSize 
         */
        bucketSort:function(arr, bucketSize) {
            if (arr.length === 0) {
              return arr;
            }
         
            var i;
            var minValue = arr[0];
            var maxValue = arr[0];
            for (i = 1; i < arr.length; i++) {
              if (arr[i] < minValue) {
                  minValue = arr[i];                //输入数据的最小值
              } else if (arr[i] > maxValue) {
                  maxValue = arr[i];                //输入数据的最大值
              }
            }
         
            //桶的初始化
            var DEFAULT_BUCKET_SIZE = 5;            //设置桶的默认数量为5
            bucketSize = bucketSize || DEFAULT_BUCKET_SIZE;
            var bucketCount = Math.floor((maxValue - minValue) / bucketSize) + 1;  
            var buckets = new Array(bucketCount);
            for (i = 0; i < buckets.length; i++) {
                buckets[i] = [];
            }
         
            //利用映射函数将数据分配到各个桶中
            for (i = 0; i < arr.length; i++) {
                buckets[Math.floor((arr[i] - minValue) / bucketSize)].push(arr[i]);
            }
         
            arr.length = 0;
            for (i = 0; i < buckets.length; i++) {
                insertionSort(buckets[i]);                      //对每个桶进行排序，这里使用了插入排序
                for (var j = 0; j < buckets[i].length; j++) {
                    arr.push(buckets[i][j]);                     
                }
            }
         
            return arr;
        },

        radixSort:function(arr, maxDigit) {
            var mod = 10;
            var dev = 1;
            for (var i = 0; i < maxDigit; i++, dev *= 10, mod *= 10) {
                for(var j = 0; j < arr.length; j++) {
                    var bucket = parseInt((arr[j] % mod) / dev);
                    if(counter[bucket]==null) {
                        counter[bucket] = [];
                    }
                    counter[bucket].push(arr[j]);
                }
                var pos = 0;
                for(var j = 0; j < counter.length; j++) {
                    var value = null;
                    if(counter[j]!=null) {
                        while ((value = counter[j].shift()) != null) {
                              arr[pos++] = value;
                        }
                  }
                }
            }
            return arr;
        }
    }
})