js 排序算法

2018-03-23  本文已影响0人  蘑菇酱960903
 /*生成一个[min,max)的随机数*/
        function randomNum1(min, max) {
            return Math.floor(Math.random()*(max - min + 1) + min);
        }
  /*生成array数组*/
        function array(min,max,count) {
            var i = 1, arr = [];
            while (i++ <= count) {
                arr.push(randomNum1(min,max));
            }
            return arr;
        }

        /*冒泡排序*/
        function bubbleSort(arr) {
            var len = arr.length, temp; 
            for (var i = 0; i < len-1; i++) {
                for (var j = i+1; j < len; j++){
                    if (arr[i] > arr[j]) {
                        temp = arr[j];
                        arr[j] = arr[i];
                        arr[i] = temp;
                    }
                }
            }
            return arr;
        }
    /*选择排序*/
    function selectSort(arr) {
        var len = arr.length, temp, flag;
        for (var i = 0; i < len-1; i++) {
            flag = i;
            for (var j = i+1; j < len; j++) {
                if (arr[flag] > arr[j]) {
                    flag = j;
                }
            }
            if (flag !== i) {
                temp = arr[flag];
                arr[flag] = arr[i];
                arr[i] = temp;
            }
        }
        return arr;
    }
        /*插入排序*/
        function insertSort(arr) {
            var len = arr.length, temp;
            for (var i = 1; i < len; i++) {
                temp = arr[i];
                for (var j = i; j > 0; j--) {
                    if (temp < arr[j-1]) {
                        arr[j] = arr[j-1];
                        arr[j-1] = temp;
                    }
                }
            }
            return arr;
        }

    /*二分排序*/
    function sort(arr) {
        var len = arr.length;
        for (var i = 1; i < len; i++) {
            var low, high, mid;
            low = 0;
            high = i-1;
            var temp = arr[i];
            while (low <= high) {
                mid = Math.floor((low + high) / 2);
                if (arr[mid] > temp) {
                    high = mid - 1;
                } else {
                    low = mid + 1;
                }
            }
            for (var j = i - 1; j > high; j--) {
                arr[j + 1] = arr[j];
            }
            arr[high + 1] = temp;
        }
        return arr;
    }
        /*快速排序*/
        /*
        利用递归方法
        先选出temp = arr[low],low指向最小值,high指向最大值
        不断让arr[low] arr[high] 与temp比较,将数组分成两个部分,左边为都小于temp的数,右边为都大于temp的数,
        再继续递归,先把左边小于temp再一次操作,选出low,temp,high…… 然后右边操作
        */
        function quickSort(arr, low, high) {
            if (low < high) {               
                var pre = Partition(arr, low, high);
                quickSort(arr, low, pre-1);
                quickSort(arr, pre+1, high);
            }
        }
        function Partition(arr, low, high) {
            var temp = arr[low];
            while (low < high) {
                while (low < high && arr[high] >= temp) {
                    high--;
                }
                if (low < high) {
                    arr[low++] = arr[high];
                }
                while (low < high && arr[low] <= temp) {
                    low++;
                }
                if (low < high) {
                    arr[high--] = arr[low];
                }
            }
            arr[low] = temp;
            return low;
        }
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