數據結構中的各類排序方法-JS實現

新技術一直在不斷變化，掌握一些基礎是將來學習不斷更新的技術的堅實基礎。近來閒來無事,爲了溫習一下從前學的數據結構，將數據結構中的排序算法用JS實現了一遍，並在本文末尾處嵌入了DEMO。

 
簡單排序
冒泡排序
     冒泡排序是最簡單排序算法,時間複雜度爲n的平方,代碼以下:

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

                }
                /* 輸出結果 */
                document.write("這是第 + (i + 1) + "次循環·，結果爲:");
                for (var k = 0; k < array.length; k++) {
                    document.write(array[k] + ",");
                }
                document.write("<br />");
                /* 輸出結果結束 */
            }
        }
 

直接插入排序
    直接插入排序也屬於簡單排序算法,時間複雜度也爲n的平方，但性能略好於冒泡排序，代碼以下:

        function insertSort(array) {
            var temp;
            for (var i = 1; i < array.length; i++) {
                var temp = array[i];
                for (var j = i; j > 0 && temp < array[j - 1]; j--) {
                    array[j] = array[j - 1];
                }
                array[j] = temp www.2cto.com
                /* 輸出結果 */
                document.write("第? + i + "遍排序的結果是:")
                for (var n = 0; n < array.length; n++) {
                    document.write(array[n] + ",");
                }

                document.write("<br />")
                /* 輸出結果結束 */

            }
        }

選擇排序
    選擇排序也屬於簡單排序算法，時間複雜度也爲n的平方，性能一樣略微好於冒泡排序，代碼以下:

        function selectSort(array) {
            var min, temp; ;
            for (var i = 0; i < array.length; i++) {
                min = i;
                for (var j = i + 1; j < array.length; j++) {
                    if (array[min] > array[j])
                        min = j;
                }
                if (min != i) {
                    temp = array[i];
                    array[i] = array[min];
                    array[min] = temp;
                }
                /* 輸出結果 */
                document.write("第 + i + "遍排序的結果是:")
                for (var n = 0; n < array.length; n++) {
                    document.write(array[n] + ",");
                }

                document.write("<br />")
                /* 輸出結果結束 */

            }
        }

複雜排序
 

希爾排序
     希爾排序是插入排序的升級，1959年希爾經過將簡單排序中兩兩比較改成設置步長跳躍式比較而突破了n的平方的時間複雜度,希爾排序根據步長的不一樣時間複雜度由最好的nlogn到最壞的n的平方。代碼以下:

       function shallSort(array) {
           var increment = array.length;
           var i
           var temp; //暫存
           var count = 0;
           do {
               increment = Math.floor(increment / 3) + 1;
               for (i = increment; i < array.length; i++) {
                   if (array[i] < array[i - increment]) {
                       temp = array[i];
                       for (var j = i - increment; j > 0 && temp < array[j]; j -= increment) {

                           array[j + increment] = array[j];

                       }
                       array[j + increment] = temp;
                       /* 輸出結果 */
                       count++;
                       document.write("<br />第 + count + "遍排序的結果是:")
                       for (var n = 0; n < array.length; n++) {
                           document.write(array[n] + ",");
                       }
                       /* 輸出結果結束 */
                   }
               }
           }
           while (increment > 1)

       }

堆排序
      堆排序是選擇排序的升級，經過不斷構建大頂堆或者小頂堆來選擇最大或者最小的值放入隊列前端進行排序，堆排序任何狀況下的時間複雜度都爲n的平方，代碼以下:

        function heapSort(array) {
            var temp;
            var i;
            for (i = Math.floor(array.length / 2); i >= 0; i--) {
                heapAdjust(array, i, array.length - 1); //將數組array構建成一個大頂堆
            }
            for (i = array.length - 1; i >= 0; i--) {
                /*把根節點交換出去*/
                temp = array[i];
                array[i] = array[0];
                array[0] = temp;

                /*餘下的數組繼續構建成大頂堆*/
                heapAdjust(array, 0, i - 1);
                /* 輸出結果 */
                document.write("<br />第 + (array.length - i).toString() + "遍排序的結果是:")
                for (var n = 0; n < array.length; n++) {
                    document.write(array[n] + ",");
                }
                /* 輸出結果結束 */
            }
        }
        //要調整的子樹
        //start爲數組開始下標
        //max是數組結束下標
        function heapAdjust(array, start, max) {
            var temp, j;
            temp = array[start];//temp是根節點的值
            for (j = 2 * start; j < max; j *= 2) {
                if (j < max && array[j] < array[j + 1]) {  //取得較大孩子的下標
                    ++j;

                }
                if (temp >= array[j])
                    break;
                array[start] = array[j];
                start = j;
            }
            array[start] = temp;

        }

歸併排序
     歸併排序是複雜排序中惟一一個穩定排序，經過將待排序數組進行分拆再合併來進行排序，歸併排序時間複雜度爲n的平方，代碼以下:

        //source源數組        //dest目標數組
        //s起始下標
        //t目標下標
        function mSort(source, dest, s, t) {
            var m; //取中間值
            var dest2 = new Array();
            if (s == t) {
                dest[s] = source[s];
            
            }
            else {
                m = Math.floor((s + t) / 2);
                mSort(source, dest2, s, m);
                mSort(source, dest2, m+1 , t);
                merge(dest2, dest, s, m, t);
                /* 輸出結果 */
                document.write("<br />第 + ++count + "遍排序的結果是:")
                for (var n = 0; n < dest.length; n++) {
                    document.write(array[n] + ",");
                }
                /* 輸出結果結束 */
            }

        }
       
        //將兩個數組按照從小到大的順序融合
        //source原數組
        //dest排序後的數組
        //s第一個下標
        //m第二個數組下標
        //總長度
        function merge(source, dest, s, m, n) {
            for (var j = m+1, k = s; j <= n && s <= m; k++) {
                if (source[s] < source[j]) {
                    dest[k] = source[s++];
                }
                else {
                    dest[k] = source[j++];
                }
            }
          
                //將剩餘排不完的有序數組加入到dest的末端
                if (s <= m) {
                    for (var l = 0; l <= m - s; l++) {
                        dest[k + l] = source[s+l];
                    }
                }
                if (j <= n) {
                    for (var l = 0; l <= n - j; l++) {
                        dest[k + l] = source[j+l];
                    }
               
            }
        }

快速排序
     快速排序是目前已知的速度最快的排序，時間複雜度爲nlogn,代碼以下:

        var count = 0;
        function quickSort(array, low, high) {
            var temp;
           
            if (low < high) {

                var keypoint = QuickSortHelp(array, low, high);
                count++;
                document.write("<br />第臺? + count + "遍括?排?序ò的?結á果?是?:")
                for (var l = 0; l < array.length; l++) {
                    document.write(array[l] + ",");
                }
                quickSort(array, low, keypoint - 1);
                quickSort(array, keypoint + 1, high);
               

                }
        }
        function QuickSortHelp(array, low, high) {
            while (low < high) {

                while (low < high && array[low] <= array[high]) {
                    high--;
                }
                temp = array[low];
                array[low] = array[high];
                array[high] = temp;
                while (low < high && array[low] <= array[high]) {
                    low++
                }
                temp = array[low];
                array[low] = array[high];
                array[high] = temp;

            }
            return low;
        }

摘自 www.cnblogs.com/CareySon