C# 经典排序算法大全

C# 经典排序算法大全

选择排序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace sorter
{
    public class SelectionSorter
    {
        private int min;
        public void Sort(int[] arr)
        {
            for (int i = 0; i < arr.Length - 1; ++i)
            {
                min = i;
                for (int j = i + 1; j < arr.Length; ++j)
                {
                    if (arr[j] < arr[min])
                    {
                        min = j;
                    }
                }
                int t = arr[min];
                arr[min] = arr[i];
                arr[i] = t;
            }
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            int[] arrInt = new int[] { 4, 2, 7, 1, 8, 3, 9, 0, 5, 6 };
            SelectionSorter selSor = new SelectionSorter();
            selSor.Sort(arrInt);
            foreach (int i in arrInt)
            {
                Console.WriteLine(i);
            }
            Console.ReadKey();
        }
    }
}

冒泡排序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace sorter
{
    public class EbullitionSorter
    {
        public void Sort(int[] arr)
        {
            int i, j, temp;
            bool done = false;
            j = 1;
            while ((j < arr.Length) && (!done))  // 推断长度
            {
                done = true;
                for (i = 0; i < arr.Length - j; i++)
                {
                    if (arr[i] > arr[i + 1])
                    {
                        done = false;
                        temp = arr[i];
                        arr[i] = arr[i + 1]; // 交换数据
                        arr[i + 1] = temp;
                    }
                }
                j++;
            }
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            int[] arrInt = new int[] { 4, 2, 7, 1, 8, 3, 9, 0, 5, 6 };
            EbullitionSorter selSor = new EbullitionSorter();
            selSor.Sort(arrInt);
            foreach (int i in arrInt)
            {
                Console.WriteLine(i);
            }
            Console.ReadKey();
        }
    }
}

高速排序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace sorter
{
    public class QuickSorter
    {
        private void swap(ref int l, ref int r)
        {
            int temp;
            temp = l;
            l = r;
            r = temp;
        }

        public void Sort(int[] list, int low, int high)
        {
            int pivot; // 存储分支点
            int l, r;
            int mid;
            if (high <= low)
            {
                return;
            }
            else if (high == low + 1)
            {
                if (list[low] > list[high])
                {
                    swap(ref list[low], ref list[high]);
                }
                return;
            }
            mid = (low + high) >> 1;
            pivot = list[mid];
            swap(ref list[low], ref list[mid]);
            l = low + 1;
            r = high;
            do
            {
                while (l <= r && list[l] < pivot)
                {
                    l++;
                }
                while (list[r] >= pivot)
                {
                    r--;
                }
                if (l < r)
                {
                    swap(ref list[l], ref list[r]);
                }
            } while (l < r);
            list[low] = list[r];
            list[r] = pivot;
            if (low + 1 < r)
            {
                Sort(list, low, r - 1);
            }
            if (r + 1 < high)
            {
                Sort(list, r + 1, high);
            }
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            int[] arrInt = new int[] { 4, 2, 7, 1, 8, 3, 9, 0, 5, 6 };
            QuickSorter selSor = new QuickSorter();
            selSor.Sort(arrInt, 0, arrInt.Length - 1);
            foreach (int i in arrInt)
            {
                Console.WriteLine(i);
            }
            Console.ReadKey();
        }
    }
}

插入排序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace sorter
{
    public class InsertionSorter
    {
        public void Sort(int[] arr)
        {
            for (int i = 1; i < arr.Length; i++)
            {
                int t = arr[i];
                int j = i;
                while ((j > 0) && (arr[j - 1] > t))
                {
                    arr[j] = arr[j - 1]; // 交换顺序
                    --j;
                }
                arr[j] = t;
            }
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            int[] arrInt = new int[] { 4, 2, 7, 1, 8, 3, 9, 0, 5, 6 };
            InsertionSorter selSor = new InsertionSorter();
            selSor.Sort(arrInt);
            foreach (int i in arrInt)
            {
                Console.WriteLine(i);
            }
            Console.ReadKey();
        }
    }
}

希尔排序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace sorter
{
    public class ShellSorter
    {
        public void Sort(int[] arr)
        {
            int inc;
            for (inc = 1; inc <= arr.Length / 9; inc = 3 * inc + 1) ;
            for (; inc > 0; inc /= 3)
            {
                for (int i = inc + 1; i <= arr.Length; i += inc)
                {
                    int t = arr[i - 1];
                    int j = i;
                    while ((j > inc) && (arr[j - inc - 1] > t))
                    {
                        arr[j - 1] = arr[j - inc - 1]; // 交换数据
                        j -= inc;
                    }
                    arr[j - 1] = t;
                }
            }
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            int[] arrInt = new int[] { 4, 2, 7, 1, 8, 3, 9, 0, 5, 6 };
            ShellSorter selSor = new ShellSorter();
            selSor.Sort(arrInt);
            foreach (int i in arrInt)
            {
                Console.WriteLine(i);
            }
            Console.ReadKey();
        }
    }
}

归并排序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Merge
{
    public class Function
    {
        private int Groups;
        private int CopyGroups;
        private int mergerows;
        private int[] Array27;
        private static Random ran = new Random();
        public Function(int length)
        {
            Array27 = new int[length];
            for (int i = 0; i < length; i++)
                Array27[i] = ran.Next(1, 100);
        }
        //选择
        public void ToMergeSort()
        {
            MergeSort(Array27);
        }
        public void ToRecursiveMergeSort()
        {
            RecursiveMergeSort(Array27, 0, Array27.Length - 1);
        }
        public void ToNaturalMergeSort()
        {
            NaturalMergeSort(Array27);
        }

        /// <summary>
        /// 归并排序(递归）
        ///    核心思想：（分治）
        ///           将待排序元素（递归直至元素个数为１）分成左右两个大小大致同样的2个子集合。然后。
        ///           分别对2个子集合进行排序，终于将排好序的子集合合并成为所要求的排好序的集合．
        /// 核心算法时间复杂度：
        ///           T(n)=O(nlogn)
        /// </summary>
        /// <param name="Array"></param>
        /// <param name="left"></param>
        /// <param name="right"></param>
        public void RecursiveMergeSort(int[] Array, int left, int right)
        {
            int middle = (left + right) / 2;

            if (left < right)
            {
                //对前半部分递归拆分
                RecursiveMergeSort(Array, left, middle);
                //对后半部分递归拆分
                RecursiveMergeSort(Array, middle + 1, right);
                MergeOne(Array, left, middle, right);
            }
        }
        public void MergeOne(int[] Array, int left, int middle, int right)
        {
            int leftindex = left;
            int rightindex = middle + 1;
            //动态暂时二维数组存放切割为两个小Array的数组排列顺序后的数据
            int[] merge = new int[right + 1];
            int index = 0;
            //对两个小数组合并排序
            while (leftindex <= middle && rightindex <= right)
                merge[index++] = (Array[leftindex] - Array[rightindex]) >= 0 ? Array[rightindex++] : Array[leftindex++];
            //有一側子数列遍历完后，将另外一側子数列剩下的数依次放入暂存数组中（有序）
            if (leftindex <= middle)
            {
                for (int i = leftindex; i <= middle; i++)
                    merge[index++] = Array[i];
            }
            if (rightindex <= right)
            {
                for (int i = rightindex; i <= right; i++)
                    merge[index++] = Array[i];
            }
            //将有序的数列 写入目标数组 ，即原来把Array数组分为两个小Array数组后又一次有序组合起来(覆盖原数组）
            index = 0;
            for (int i = left; i <= right; i++)
                Array[i] = merge[index++];
        }

        /// <summary>
        /// 归并排序(非递归）
        ///     核心思想：（分治）
        ///           对n个数的数列每相邻两个元素排序。组成n/2个或（n+1)/2个子数组，单个的不比了直接进入下一轮。
        ///     然后对每一个相邻的子数组再排序，以此类推最后得到排好序的数列
        ///  forexample：  59 35 54 28 52
        ///   排序And分：  35 59. 28 54. 52
        ///   排序And分：  28 35 54 59. 52
        ///        结果：  28 35 52 54 59
        /// 核心算法时间复杂度：
        ///           T(n)=O(nlogn)
        /// </summary>
        /// <param name="Array"></param>
        public void MergeSort(int[] Array)
        {
            //index固定的数组
            int[] merge = new int[Array.Length];
            int P = 0;
            while (true)
            {
                int index = 0;
                //子数组元素的个数
                int ENumb = (int)Math.Pow(2, P);
                //一个子数组中的元素个数与数组的一半元素个数比較大小
                //最糟糕的情况最右边的数组仅仅有一个元素
                if (ENumb < Array.Length)
                {
                    while (true)
                    {
                        int TorFAndrightindex = index;
                        //最后一个子数组的第一个元素的index与数组index相比較
                        if (TorFAndrightindex <= Array.Length - 1)
                            MergeTwo(Array, merge, index, ENumb);
                        else
                            break;
                        index += 2 * ENumb;
                    }
                }
                else
                    break;
                P++;
            }
        }
        public void MergeTwo(int[] Array, int[] merge, int index, int ENumb)
        {
            //换分两个子数组的index(千万不能用middle = (right + left) / 2划分）
            // 1
            int left = index;
            int middle = left + ENumb - 1;
            //（奇数时）
            //排除middleindex越界
            if (middle >= Array.Length)
            {
                middle = index;
            }
            //同步化merge数组的index
            int mergeindex = index;
            // 2
            int right;
            int middleTwo = (index + ENumb - 1) + 1;
            right = index + ENumb + ENumb - 1;
            //排除最后一个子数组的index越界.
            if (right >= Array.Length - 1)
            {
                right = Array.Length - 1;
            }
            //排序两个子数组并拷贝到merge数组
            while (left <= middle && middleTwo <= right)
            {
                merge[mergeindex++] = Array[left] >= Array[middleTwo] ? Array[middleTwo++] : Array[left++];
            }
            //两个子数组中当中一个比較完了（Array[middleTwo++] 或Array[left++]）。
            //把当中一个数组中剩下的元素复制进merge数组。
            if (left <= middle)
            {
                //排除空元素.
                while (left <= middle && mergeindex < merge.Length)
                    merge[mergeindex++] = Array[left++];
            }
            if (middleTwo <= right)
            {
                while (middleTwo <= right)
                    merge[mergeindex++] = Array[middleTwo++];
            }
            //推断是否合并至最后一个子数组了
            if (right + 1 >= Array.Length)
                Copy(Array, merge);
        }

        /// <summary>
        /// 自然归并排序:
        ///      对于初始给定的数组,通常存在多个长度大于1的已自然排好序的子数组段.
        /// 比如,若数组a中元素为{4,8,3,7,1,5,6,2},则自然排好序的子数组段
        /// 有{4,8},{3,7},{1,5,6},{2}.
        /// 用一次对数组a的线性扫描就足以找出全部这些排好序的子数组段.
        /// 然后将相邻的排好序的子数组段两两合并,
        /// 构成更大的排好序的子数组段({3,4,7,8},{1,2,5,6}).
        /// 继续合并相邻排好序的子数组段,直至整个数组已排好序.
        /// 核心算法时间复杂度：
        ///        T(n)=○(n);
        /// </summary>
        public void NaturalMergeSort(int[] Array)
        {
            //得到自然划分后的数组的index组（每行为一个自然子数组）
            int[,] PointsSymbol = LinearPoints(Array);
            //子数组仅仅有一个。
            if (PointsSymbol[0, 1] == Array.Length - 1)
                return;
            //多个(至少两个子数组）...
            else
                //能够堆栈调用吗？
                NaturalMerge(Array, PointsSymbol);

        }
        public void NaturalMerge(int[] Array, int[,] PointsSymbol)
        {
            int left;
            int right;
            int leftend;
            int rightend;

            mergerows = GNumberTwo(Groups);
            CopyGroups = Groups;
            //固定状态
            int[] TempArray = new int[Array.Length];
            //循环取每一个自然子数组的index
            while (true)
            {
                // int Temprow = 1;
                //仅仅记录合并后的子数组(”《应该为》“动态的）
                int[,] TempPointsSymbol = new int[mergerows, 2];

                int row = 0;
                do
                {
                    //最重要的推断：最后(一组子数组)是否可配对
                    if (row != CopyGroups - 1)
                    { //以上条件也能够含有(& 和&&的差别)短路运算
                        //參考:http://msdn.microsoft.com/zh-cn/library/2a723cdk(VS.80).aspx
                        left = PointsSymbol[row, 0];
                        leftend = PointsSymbol[row, 1];
                        right = PointsSymbol[row + 1, 0];
                        rightend = PointsSymbol[row + 1, 1];
                        MergeThree(Array, TempArray, left, leftend, right, rightend);
                        MergePointSymbol(PointsSymbol, TempPointsSymbol, row);
                    }
                    else
                    {
                        ////默认剩下的单独一个子数组已经虚拟合并。然后Copy进TempArray。
                        int TempRow = PointsSymbol[row, 0];
                        int TempCol = PointsSymbol[row, 1];
                        while (TempRow <= TempCol)
                            TempArray[TempRow] = Array[TempRow++];
                        //TempPointSymbol完整同步
                        TempPointsSymbol[row / 2, 0] = PointsSymbol[row, 0];
                        TempPointsSymbol[row / 2, 1] = PointsSymbol[row, 1];
                        break;//又一次開始新一轮循环。
                    }
                    row += 2;
                    // Temprow++;
                    //合并到仅仅有一个子数组时结束循环
                    if (TempPointsSymbol[0, 1] == Array.Length - 1)
                        break;
                }//推断别进入越界循环(能够进孤单循环）这里指的是PointsSymbol的子数组个数
                while (row <= CopyGroups - 1);
                //
                Copy(Array, TempArray);
                //更新子数组index，row为跳出循环的条件（最后单个子数组或下一个越界的第一个）
                UpdatePointSymbol(PointsSymbol, TempPointsSymbol, row);
                //改变TempPointsSymbol的行数（合并后子数组数）
                mergerows = GNumber(mergerows);
                CopyGroups = GNumberTwo(CopyGroups);
                //合并到仅仅有一个子数组时结束循环
                if (PointsSymbol[0, 1] == Array.Length - 1)
                    break;
            }
            //输出
        }
        public int GNumber(int Value)
        {
            if (Value % 2 == 0)
                Value /= 2;
            else
                Value -= 1;

            return Value;
        }
        public int GNumberTwo(int Value)
        {
            if (Value % 2 == 0)
                mergerows = Value / 2;
            else
                mergerows = Value / 2 + 1;
            return mergerows;
        }
        public void MergeThree(int[] Array, int[] Temp, int left, int leftend, int right, int rightend)
        {
            //合并语句
            int index = left;
            while (left <= leftend && right <= rightend)
                Temp[index++] = Array[left] >= Array[right] ? Array[right++] : Array[left++];
            while (left <= leftend)
                Temp[index++] = Array[left++];
            while (right <= rightend)
                Temp[index++] = Array[right++];
        }
        public void MergePointSymbol(int[,] PointsSymbol, int[,] TempPointsSymbol, int row)
        {
            int rowindex = row / 2;
            TempPointsSymbol[rowindex, 0] = PointsSymbol[row, 0];
            TempPointsSymbol[rowindex, 1] = PointsSymbol[row + 1, 1];
        }
        public void UpdatePointSymbol(int[,] PointsSymbol, int[,] TempPointsSymbol, int rows)
        {
            int row = 0;
            //if (mergerows % 2 == 0)
            //{
            for (; row < TempPointsSymbol.GetLength(0); row++)
            {
                for (int col = 0; col < 2; col++)
                    PointsSymbol[row, col] = TempPointsSymbol[row, col];
            }
            //后面的清零
            for (; row < PointsSymbol.GetLength(0); row++)
            {
                for (int col2 = 0; col2 < 2; col2++)
                    PointsSymbol[row, col2] = 0;
            }
            //}
            ////补剩下的index组，
            //else
            //{
            //    for (int row2 = 0; row2 < TempPointsSymbol.GetLength(0); row2++)
            //    {
            //        for (int col3 = 0; col3 < 2; col3++)
            //            PointsSymbol[row2, col3] = TempPointsSymbol[row2, col3];
            //    }
            //    //最后一个子数组的index仅仅有一个。

//    int row3 = TempPointsSymbol.GetLength(0);
            //    PointsSymbol[row3, 0] = PointsSymbol[rows, 0];
            //    PointsSymbol[row3, 1] = PointsSymbol[rows, 1];
            //    //后面的清零
            //    for (int row4 = row3 + 1; row4 < PointsSymbol.GetLength(0); row4++)
            //    {
            //        for (int col4 = 0; col4 < 2; col4++)
            //            PointsSymbol[row4, col4] = 0;
            //    }
            //}

        }
        public int[,] LinearPoints(int[] Array)
        {
            Groups = 1;
            int StartPoint = 0;
            int row = 0;
            int col = 0;
            //最糟糕的情况就是有Array.Length行。
            int[,] PointsSet = new int[Array.Length, 2];
            //线性扫描Array，划分数组
            //初始前index=0
            PointsSet[row, col] = 0;
            do
            {
                //推断升序子数组终于的index开关
                bool Judge = false;
                //从Array第二个数推断是否要结束或者是否是升序子数组.
                while (++StartPoint < Array.Length && Array[StartPoint] < Array[StartPoint - 1])
                {
                    //打开第一个升序子数组结束的index开关
                    Judge = true;
                    //又一次開始第二个升序子数组的前index
                    PointsSet[row, col + 1] = StartPoint - 1;
                    //计算子数组个数
                    Groups++;
                    //换行记录自然子数组的index
                    row++;
                    break;
                    //--StartPoint;
                }
                //升序子数组结束index
                if (Judge)
                    PointsSet[row, col] = StartPoint;
                //else
                //    --StartPoint;
            } while (StartPoint < Array.Length);
            //终于index=StartPoint - 1，可是糟糕情况下还有剩余若干行为： 0,0 ...
            PointsSet[row, col + 1] = StartPoint - 1;
            //调用展示方法
            DisplaySubarray(Array, PointsSet, Groups);
            return PointsSet;
        }
        public void DisplaySubarray(int[] Array, int[,] PointsSet, int Groups)
        {
            Console.WriteLine("Subarray is {0}:", Groups);
            //展示子数组的前后index
            for (int r = 0; r < Groups; r++)
            {
                for (int c = 0; c < PointsSet.GetLength(1); c++)
                {
                    Console.Write(PointsSet[r, c]);
                    if (c < PointsSet.GetLength(1) - 1)
                        Console.Write(",");
                }
                Console.Write("\t\t");
            }
            Console.WriteLine();
            //展示分出的子数组
            for (int v = 0; v < Groups; v++)
            {
                int i = 1;
                for (int r = PointsSet[v, 0]; r <= PointsSet[v, 1]; r++)
                {
                    Console.Write(Array[r] + " ");
                    i++;
                }
                if (i <= 3)
                    Console.Write("\t\t");
                else
                    Console.Write("\t");
                if (PointsSet[v, 1] == Array.Length)
                    break;
            }
        }

        public void Copy(int[] Array, int[] merge)
        {
            //一部分排好序的元素替换掉原来Array中的元素
            for (int i = 0; i < Array.Length; i++)
            {
                Array[i] = merge[i];
            }
        }
        //输出
        public override string ToString()
        {
            string temporary = string.Empty;

            foreach (var element in Array27)
                temporary += element + " ";

            temporary += "\n";
            return temporary;
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            while (true)
            {
                Console.WriteLine("请选择：");
                Console.WriteLine("1.归并排序（非递归）");
                Console.WriteLine("2.归并排序（递归）");
                Console.WriteLine("3.归并排序（自然合并）");
                Console.WriteLine("4.退出");
                int Arraynum = Convert.ToInt32(Console.ReadLine());
                switch (Arraynum)
                {
                    case 4:
                        Environment.Exit(0);
                        break;
                    case 1:
                        Console.WriteLine("Please Input Array Length");
                        int Leng271 = Convert.ToInt32(Console.ReadLine());
                        Function obj1 = new Function(Leng271);

                        Console.WriteLine("The original sequence:");
                        Console.WriteLine(obj1);
                        Console.WriteLine("'MergeSort' Finaly Sorting Result:");
                        obj1.ToMergeSort();
                        Console.WriteLine(obj1);
                        break;
                    case 2:
                        Console.WriteLine("Please Input Array Length");
                        int Leng272 = Convert.ToInt32(Console.ReadLine());
                        Function obj2 = new Function(Leng272);

                        Console.WriteLine("The original sequence:");
                        Console.WriteLine(obj2);
                        Console.WriteLine("'RecursiveMergeSort' Finaly Sorting Result:");
                        obj2.ToRecursiveMergeSort();
                        Console.WriteLine(obj2);
                        break;
                    case 3:
                        Console.WriteLine("Please Input Array Length");
                        int Leng273 = Convert.ToInt32(Console.ReadLine());
                        Function obj3 = new Function(Leng273);

                        Console.WriteLine("The original sequence:");
                        Console.WriteLine(obj3);
                        obj3.ToNaturalMergeSort();
                        Console.WriteLine(); Console.WriteLine();
                        Console.WriteLine("'NaturalMergeSort' Finaly Sorting Result:");
                        Console.WriteLine(obj3);
                        break;
                }
            }
        }
    }
}

基数排序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Merge
{
    public class RadixSorter
    {
        //基数排序
        public int[] RadixSort(int[] ArrayToSort, int digit)
        {
            //low to high digit
            for (int k = 1; k <= digit; k++)
            {
                //temp array to store the sort result inside digit
                int[] tmpArray = new int[ArrayToSort.Length];
                //temp array for countingsort
                int[] tmpCountingSortArray = new int[10] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
                //CountingSort
                for (int i = 0; i < ArrayToSort.Length; i++)
                {
                    //split the specified digit from the element
                    int tmpSplitDigit = ArrayToSort[i] / (int)Math.Pow(10, k - 1) - (ArrayToSort[i] / (int)Math.Pow(10, k)) * 10;
                    tmpCountingSortArray[tmpSplitDigit] += 1;
                }
                for (int m = 1; m < 10; m++)
                {
                    tmpCountingSortArray[m] += tmpCountingSortArray[m -
                    1];
                }
                //output the value to result
                for (int n = ArrayToSort.Length - 1; n >= 0; n--)
                {
                    int tmpSplitDigit = ArrayToSort[n] / (int)Math.Pow(10, k - 1) -
                    (ArrayToSort[n] / (int)Math.Pow(10, k)) * 10;
                    tmpArray[tmpCountingSortArray[tmpSplitDigit] - 1] = ArrayToSort
                    [n];
                    tmpCountingSortArray[tmpSplitDigit] -= 1;
                }
                //copy the digit-inside sort result to source array
                for (int p = 0; p < ArrayToSort.Length; p++)
                {
                    ArrayToSort[p] = tmpArray[p];
                }
            }
            return ArrayToSort;
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            int[] intArray = new int[] { 5, 3, 7, 4, 8, 2, 9, 1, 0, 6 };
            int[] newIntArray = intArray;
            RadixSorter rS=new RadixSorter();
            newIntArray = rS.RadixSort(intArray, intArray.Length);
            foreach (int i in intArray)
            {
                Console.Write(i + " ");
            }
            Console.ReadKey();
        }
    }
}

计数排序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Merge
{
    class Program
    {
        /// <summary>
        /// 计数排序。

/// 要求:
        ///     arrayToSort的元素必须大于等于0。或者经过一定的转换使其元素在
        ///     大于等于0范围内。比如有例如以下序列(-1,-8,10,11),那么依据最小值8,
        ///     将各个数字加8转化为(7,0,18,19),然后进行计数排序。结果为(0,7,18,19),
        ///     然后再将结果个数字减8即为(-8,-1,10,11)
        /// </summary>
        /// <param name="arrayToSort">要排序的数组</param>
        /// <param name="maxValue">数组的最大值加一</param>
        /// <returns>计数排序后的结果</returns>
        public static int[] CountingSort(int[] arrayToSort, int k)
        {
            // 排序后的结果存储
            int[] sortedArray = new int[arrayToSort.Length];
            // 计数数组
            int[] countingArray = new int[k];
            // 计数数组初始化
            for (int i = 0; i < countingArray.Length; i++)
            {
                countingArray[i] = 0;
            }

            // 单个元素计数(经过该步骤countingArray[i]的含义为数字i的个数为countingArray[i])
            for (int i = 0; i < arrayToSort.Length; i++)
            {
                countingArray[arrayToSort[i]] = countingArray[arrayToSort[i]] + 1;
            }
            // 计算小于等于某数的个数(经过该步骤countingArray[i]的含义为小于等于数字i的元素个数为countingArray[i])
            for (int i = 1; i < countingArray.Length; i++)
            {
                countingArray[i] += countingArray[i - 1];
            }

            // 得到排序后的结果
            for (int i = 0; i < sortedArray.Length; i++)
            {
                int numIndex = countingArray[arrayToSort[i]] - 1;
                sortedArray[numIndex] = arrayToSort[i];
                countingArray[arrayToSort[i]] = countingArray[arrayToSort[i]] - 1;
            }

            return sortedArray;
        }

        static void Main(string[] args)
        {
            int[] intArray = new int[] { 5, 3, 7, 4, 8, 2, 9, 1, 0, 6 };
            int[] intNewArray = intArray;
            intNewArray = CountingSort(intArray, intArray.Length);
            foreach (int i in intNewArray)
            {
                Console.Write(i + " ");
            }
            Console.ReadKey();
        }
    }
}

堆排序

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Merge
{
    class Program
    {
        //堆排序算法（传递待排数组名，即：数组的地址。故形參数组的各种操作反应到实參数组上）
        private static void HeapSortFunction(int[] array)
        {
            try
            {
                BuildMaxHeap(array);    //创建大顶推（初始状态看做：总体无序）
                for (int i = array.Length - 1; i > 0; i--)
                {
                    Swap(ref array[0], ref array[i]); //将堆顶元素依次与无序区的最后一位交换（使堆顶元素进入有序区）
                    MaxHeapify(array, 0, i); //又一次将无序区调整为大顶堆
                }
            }
            catch (Exception ex)
            {
                Console.Write(ex.Message);
            }
        }

        ///<summary>
        /// 创建大顶推（根节点大于左右子节点）
        ///</summary>
        ///<param name="array">待排数组</param>
        private static void BuildMaxHeap(int[] array)
        {
            try
            {
                //依据大顶堆的性质可知：数组的前半段的元素为根节点，其余元素都为叶节点
                for (int i = array.Length / 2 - 1; i >= 0; i--) //从最底层的最后一个根节点開始进行大顶推的调整
                {
                    MaxHeapify(array, i, array.Length); //调整大顶堆
                }
            }
            catch (Exception ex)
            {
                Console.Write(ex.Message);
            }
        }

        ///<summary>
        /// 大顶推的调整过程
        ///</summary>
        ///<param name="array">待调整的数组</param>
        ///<param name="currentIndex">待调整元素在数组中的位置（即：根节点）</param>
        ///<param name="heapSize">堆中全部元素的个数</param>
        private static void MaxHeapify(int[] array, int currentIndex, int heapSize)
        {
            try
            {
                int left = 2 * currentIndex + 1;    //左子节点在数组中的位置
                int right = 2 * currentIndex + 2;   //右子节点在数组中的位置
                int large = currentIndex;   //记录此根节点、左子节点、右子节点 三者中最大值的位置

                if (left < heapSize && array[left] > array[large])  //与左子节点进行比較
                {
                    large = left;
                }
                if (right < heapSize && array[right] > array[large])    //与右子节点进行比較
                {
                    large = right;
                }
                if (currentIndex != large)  //假设 currentIndex != large 则表明 large 发生变化（即：左右子节点中有大于根节点的情况）
                {
                    Swap(ref array[currentIndex], ref array[large]);    //将左右节点中的大者与根节点进行交换（即：实现局部大顶堆）
                    MaxHeapify(array, large, heapSize); //以上次调整动作的large位置（为此次调整的根节点位置），进行递归调整
                }
            }
            catch (Exception ex)
            {
                Console.Write(ex.Message);
            }
        }

        ///<summary>
        /// 交换函数
        ///</summary>
        ///<param name="a">元素a</param>
        ///<param name="b">元素b</param>
        private static void Swap(ref int a, ref int b)
        {
            int temp = 0;
            temp = a;
            a = b;
            b = temp;
        }

        static void Main(string[] args)
        {
            int[] intArray = new int[] { 5, 3, 7, 4, 8, 2, 9, 1, 0, 6 };
            HeapSortFunction(intArray);
            foreach (int i in intArray)
            {
                Console.Write(i + " ");
            }
            Console.ReadKey();
        }
    }
}

排序的分类/稳定性/时间复杂度和空间复杂度总结

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