CSharp: Sorting Algorithms

 

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/*****************************************************************//**  * \file    SortingAlgorithm.cs  * \brief  csharp Sorting Algorithms 算法  * IDE  vs 2022 C#  .net 6.0  * \author geovindu,Geovin Du,涂聚文  * \date   September 28 2023  *********************************************************************/     using System.Collections.Generic; using System.Collections;     /**  *  */ namespace SortingAlgorithms {       /// <summary>     /// 排序算法     /// </summary>     public class SortingAlgorithm     {               /// <summary>         /// 1.Bubble Sort冒泡排序法         /// </summary>         /// <param name="arr"></param>              public static void BubbleSort(int[] arrry)         {             int n = arrry.Length;             int i, j, temp;             bool swapped;             for (i = 0; i < n - 1; i++)             {                 swapped = false;                 for (j = 0; j < n - i - 1; j++)                 {                     if (arrry[j] > arrry[j + 1])                     {                           // Swap arr[j] and arr[j+1]                         temp = arrry[j];                         arrry[j] = arrry[j + 1];                         arrry[j + 1] = temp;                         swapped = true;                     }                 }                   // If no two elements were                 // swapped by inner loop, then break                 if (swapped == false)                     break;             }         }         /// <summary>         /// 打印数组内容         /// </summary>         /// <param name="arrry"></param>          public static void printArray(int[] arrry)         {             int i;             int size = arrry.Length;             for (i = 0; i < size; i++)                 Console.Write(arrry[i] + " ");             Console.WriteLine();         }           /// <summary>         /// 2.Selection Sort 选择排序         ///         /// </summary>         /// <param name="arr"></param>         public static void SelectionSort(int[] arrry)         {             int n = arrry.Length;               // One by one move boundary of unsorted subarray             for (int i = 0; i < n - 1; i++)             {                 // Find the minimum element in unsorted array                 int min_idx = i;                 for (int j = i + 1; j < n; j++)                     if (arrry[j] < arrry[min_idx])                         min_idx = j;                   // Swap the found minimum element with the first                 // element                 int temp = arrry[min_idx];                 arrry[min_idx] = arrry[i];                 arrry[i] = temp;             }         }         /// <summary>         /// 3. 插入排序 Insertion Sort         /// </summary>         /// <param name="arrry"></param>         public static void InsertionSort(int[] arrry)         {             int n = arrry.Length;             for (int i = 1; i < n; ++i)             {                 int key = arrry[i];                 int j = i - 1;                   // Move elements of arr[0..i-1],                 // that are greater than key,                 // to one position ahead of                 // their current position                 while (j >= 0 && arrry[j] > key)                 {                     arrry[j + 1] = arrry[j];                     j = j - 1;                 }                 arrry[j + 1] = key;             }         }           /// <summary>         /// A utility function to swap two elements         /// </summary>         /// <param name="arr"></param>         /// <param name="i"></param>         /// <param name="j"></param>         private static void quickSwap(int[] arr, int i, int j)         {             int temp = arr[i];             arr[i] = arr[j];             arr[j] = temp;         }           // This function takes last element as pivot,         // places the pivot element at its correct position         // in sorted array, and places all smaller to left         // of pivot and all greater elements to right of pivot         private static int partition(int[] arr, int low, int high)         {             // Choosing the pivot             int pivot = arr[high];               // Index of smaller element and indicates             // the right position of pivot found so far             int i = (low - 1);               for (int j = low; j <= high - 1; j++)             {                   // If current element is smaller than the pivot                 if (arr[j] < pivot)                 {                       // Increment index of smaller element                     i++;                     quickSwap(arr, i, j);                 }             }             quickSwap(arr, i + 1, high);             return (i + 1);         }           // The main function that implements QuickSort         // arr[] --> Array to be sorted,         // low --> Starting index,         // high --> Ending index         /// <summary>         /// 4 Quick Sort 快速排序         /// </summary>         /// <param name="arr"></param>         /// <param name="low"></param>         /// <param name="high"></param>         public static void quickSort(int[] arr, int low, int high)         {             if (low < high)             {                   // pi is partitioning index, arr[p]                 // is now at right place                 int pi = partition(arr, low, high);                   // Separately sort elements before                 // and after partition index                 quickSort(arr, low, pi - 1);                 quickSort(arr, pi + 1, high);             }         }             // Merges two subarrays of []arr.         // First subarray is arr[l..m]         // Second subarray is arr[m+1..r]         /// <summary>         ///         ///         /// </summary>         /// <param name="arr"></param>         /// <param name="l"></param>         /// <param name="m"></param>         /// <param name="r"></param>         private static void merge(int[] arr, int l, int m, int r)         {             // Find sizes of two             // subarrays to be merged             int n1 = m - l + 1;             int n2 = r - m;               // Create temp arrays             int[] L = new int[n1];             int[] R = new int[n2];             int i, j;               // Copy data to temp arrays             for (i = 0; i < n1; ++i)                 L[i] = arr[l + i];             for (j = 0; j < n2; ++j)                 R[j] = arr[m + 1 + j];               // Merge the temp arrays               // Initial indexes of first             // and second subarrays             i = 0;             j = 0;               // Initial index of merged             // subarray array             int k = l;             while (i < n1 && j < n2)             {                 if (L[i] <= R[j])                 {                     arr[k] = L[i];                     i++;                 }                 else                 {                     arr[k] = R[j];                     j++;                 }                 k++;             }               // Copy remaining elements             // of L[] if any             while (i < n1)             {                 arr[k] = L[i];                 i++;                 k++;             }               // Copy remaining elements             // of R[] if any             while (j < n2)             {                 arr[k] = R[j];                 j++;                 k++;             }         }           // Main function that         // sorts arr[l..r] using         // merge()         /// <summary>         /// 5 Merge Sort 合并/归并排序         /// </summary>         /// <param name="arr"></param>         /// <param name="l"></param>         /// <param name="r"></param>         public static void MergeSort(int[] arr, int l, int r)         {             if (l < r)             {                   // Find the middle point                 int m = l + (r - l) / 2;                   // Sort first and second halves                 MergeSort(arr, l, m);                 MergeSort(arr, m + 1, r);                   // Merge the sorted halves                 merge(arr, l, m, r);             }         }             /* Function to calculate length of linked list */         /// <summary>         ///         /// </summary>         /// <param name="current"></param>         /// <returns></returns>         private static int LinkedLength(Node current)         {             int count = 0;             while (current != null)             {                 current = current.next;                 count++;             }             return count;         }           /* Merge function of Merge Sort to Merge the two sorted parts         of the Linked List. We compare the next value of start1 and         current value of start2 and insert start2 after start1 if         it's smaller than next value of start1. We do this until         start1 or start2 end. If start1 ends, then we assign next         of start1 to start2 because start2 may have some elements         left out which are greater than the last value of start1.         If start2 ends then we assign end2 to end1. This is necessary         because we use end2 in another function (mergeSort function)         to determine the next start1 (i.e) start1 for next         iteration = end2.next */         private static Node LinkedMerge(Node start1, Node end1,                 Node start2, Node end2)         {               // Making sure that first node of second             // list is higher.             Node temp = null;             if ((start1).data > (start2).data)             {                 Node t = start1;                 start1 = start2;                 start2 = t;                 t = end1;                 end1 = end2;                 end2 = t;             }               // Merging remaining nodes             Node astart = start1, aend = end1;             Node bstart = start2, bend = end2;             Node bendnext = (end2).next;             while (astart != aend && bstart != bendnext)             {                 if (astart.next.data > bstart.data)                 {                     temp = bstart.next;                     bstart.next = astart.next;                     astart.next = bstart;                     bstart = temp;                 }                 astart = astart.next;             }             if (astart == aend)                 astart.next = bstart;             else                 end2 = end1;               return start1;         }           /* MergeSort of Linked List         The gap is initially 1. It is incremented as         2, 4, 8, .. until it reaches the length of the         linked list. For each gap, the linked list is         sorted around the gap.         The prevend stores the address of the last node after         sorting a part of linked list so that it's next node         can be assigned after sorting the succeeding list.         temp is used to store the next start1 because after         sorting, the last node will be different. So it         is necessary to store the address of start1 before         sorting. We select the start1, end1, start2, end2 for         sorting. start1 - end1 may be considered as a list         and start2 - end2 may be considered as another list         and we are merging these two sorted list in merge         function and assigning the starting address to the         previous end address. */           /// <summary>         /// Iterative Merge Sort for Linked List         /// </summary>         /// <param name="head"></param>         /// <returns></returns>         public static Node LinkedMergeSort(Node head)         {             if (head == null)                 return head;             Node start1 = null, end1 = null;             Node start2 = null, end2 = null;             Node prevend = null;             int len = LinkedLength(head);               for (int gap = 1; gap < len; gap = gap * 2)             {                 start1 = head;                 while (start1 != null)                 {                       // If this is first iteration                     Boolean isFirstIter = false;                     if (start1 == head)                         isFirstIter = true;                       // First part for merging                     int counter = gap;                     end1 = start1;                     while (--counter > 0 && end1.next != null)                         end1 = end1.next;                       // Second part for merging                     start2 = end1.next;                     if (start2 == null)                         break;                     counter = gap;                     end2 = start2;                     while (--counter > 0 && end2.next != null)                         end2 = end2.next;                       // To store for next iteration.                     Node temp = end2.next;                       // Merging two parts.                     LinkedMerge(start1, end1, start2, end2);                       // Update head for first iteration, else                     // append after previous list                     if (isFirstIter)                         head = start1;                     else                         prevend.next = start1;                       prevend = end2;                     start1 = temp;                 }                 prevend.next = start1;             }             return head;         }             /* Given a reference (pointer to         pointer) to the head of a list         and an int, push a new node on         the front of the list. */         /// <summary>         ///         /// </summary>         /// <param name="head_ref"></param>         /// <param name="new_data"></param>         /// <returns></returns>         public static Node LinkedPush(Node head_ref,int new_data)         {             Node new_node = new Node();             new_node.data = new_data;             new_node.next = (head_ref);             (head_ref) = new_node;             return head_ref;         }         /// <summary>         /// 6 Counting Sort 计数排序         /// </summary>         /// <param name="inputArray"></param>         /// <returns></returns>           public static List<int> countSort(List<int> inputArray)         {             int N = inputArray.Count();             int M = 0;               for (int i = 0; i < N; i++)             {                 M = Math.Max(M, inputArray[i]);             }               int[] countArray = new int[M + 1];               for (int i = 0; i < N; i++)             {                 countArray[inputArray[i]]++;             }               for (int i = 1; i <= M; i++)             {                 countArray[i] += countArray[i - 1];             }               List<int> outputArray = new List<int>();// new int[N];               for (int i = N - 1; i >= 0; i--)             {                 outputArray[countArray[inputArray[i]] - 1] = inputArray[i];                 countArray[inputArray[i]]--;             }               return outputArray;         }         /// <summary>         ///         /// </summary>         /// <param name="arr"></param>         /// <param name="n"></param>         /// <returns></returns>         public static int getMax(int[] arr, int n)         {             int mx = arr[0];             for (int i = 1; i < n; i++)                 if (arr[i] > mx)                     mx = arr[i];             return mx;         }           // A function to do counting sort of arr[] according to         // the digit represented by exp.         /// <summary>         ///         /// </summary>         /// <param name="arr"></param>         /// <param name="n"></param>         /// <param name="exp"></param>         public static void radixCountSort(int[] arr, int n, int exp)         {             int[] output = new int[n]; // output array             int i;             int[] count = new int[10];               // initializing all elements of count to 0             for (i = 0; i < 10; i++)                 count[i] = 0;               // Store count of occurrences in count[]             for (i = 0; i < n; i++)                 count[(arr[i] / exp) % 10]++;               // Change count[i] so that count[i] now contains             // actual             //  position of this digit in output[]             for (i = 1; i < 10; i++)                 count[i] += count[i - 1];               // Build the output array             for (i = n - 1; i >= 0; i--)             {                 output[count[(arr[i] / exp) % 10] - 1] = arr[i];                 count[(arr[i] / exp) % 10]--;             }               // Copy the output array to arr[], so that arr[] now             // contains sorted numbers according to current             // digit             for (i = 0; i < n; i++)                 arr[i] = output[i];         }           // The main function to that sorts arr[] of size n using         // Radix Sort         /// <summary>         ///         /// </summary>         /// <param name="arr"></param>         /// <param name="n"></param>         public static void radixSort(int[] arr, int n)         {             // Find the maximum number to know number of digits             int m = getMax(arr, n);               // Do counting sort for every digit. Note that             // instead of passing digit number, exp is passed.             // exp is 10^i where i is current digit number             for (int exp = 1; m / exp > 0; exp *= 10)                 radixCountSort(arr, n, exp);         }           // Insertion sort function to sort individual buckets          private  static void InsertionSort(List<float> bucket)         {             for (int i = 1; i < bucket.Count; ++i)             {                 float key = bucket[i];                 int j = i - 1;                 while (j >= 0 && bucket[j] > key)                 {                     bucket[j + 1] = bucket[j];                     j--;                 }                 bucket[j + 1] = key;             }         }           // Function to sort arr[] of size n using bucket sort         /// <summary>         /// 8 Bucket Sort 桶排序         /// </summary>         /// <param name="arr"></param>         public static void BucketSort(float[] arr)         {             int n = arr.Length;               // 1) Create n empty buckets             List<float>[] buckets = new List<float>[n];             for (int i = 0; i < n; i++)             {                 buckets[i] = new List<float>();             }               // 2) Put array elements in different buckets             for (int i = 0; i < n; i++)             {                 int bi = (int)(n * arr[i]);                 buckets[bi].Add(arr[i]);             }               // 3) Sort individual buckets using insertion sort             for (int i = 0; i < n; i++)             {                 InsertionSort(buckets[i]);             }               // 4) Concatenate all buckets into arr[]             int index = 0;             for (int i = 0; i < n; i++)             {                 for (int j = 0; j < buckets[i].Count; j++)                 {                     arr[index++] = buckets[i][j];                 }             }         }           /// <summary>         /// 9 Heap Sort 堆排序         /// </summary>         /// <param name="arr"></param>         public static void HeapSort(int[] arr)         {             int N = arr.Length;               // Build heap (rearrange array)             for (int i = N / 2 - 1; i >= 0; i--)                 heapify(arr, N, i);               // One by one extract an element from heap             for (int i = N - 1; i > 0; i--)             {                 // Move current root to end                 int temp = arr[0];                 arr[0] = arr[i];                 arr[i] = temp;                   // call max heapify on the reduced heap                 heapify(arr, i, 0);             }         }           // To heapify a subtree rooted with node i which is         // an index in arr[]. n is size of heap         /// <summary>         ///         /// </summary>         /// <param name="arr"></param>         /// <param name="N"></param>         /// <param name="i"></param>          private static void heapify(int[] arr, int N, int i)         {             int largest = i; // Initialize largest as root             int l = 2 * i + 1; // left = 2*i + 1             int r = 2 * i + 2; // right = 2*i + 2               // If left child is larger than root             if (l < N && arr[l] > arr[largest])                 largest = l;               // If right child is larger than largest so far             if (r < N && arr[r] > arr[largest])                 largest = r;               // If largest is not root             if (largest != i)             {                 int swap = arr[i];                 arr[i] = arr[largest];                 arr[largest] = swap;                   // Recursively heapify the affected sub-tree                 heapify(arr, N, largest);             }         }             /* function to sort arr using shellSort */         /// <summary>         /// 10 Shell Sort 希尔排序         /// </summary>         /// <param name="arr"></param>         /// <returns></returns>         public static int ShellSort(int[] arr)         {             int n = arr.Length;               // Start with a big gap,             // then reduce the gap             for (int gap = n / 2; gap > 0; gap /= 2)             {                 // Do a gapped insertion sort for this gap size.                 // The first gap elements a[0..gap-1] are already                 // in gapped order keep adding one more element                 // until the entire array is gap sorted                 for (int i = gap; i < n; i += 1)                 {                     // add a[i] to the elements that have                     // been gap sorted save a[i] in temp and                     // make a hole at position i                     int temp = arr[i];                       // shift earlier gap-sorted elements up until                     // the correct location for a[i] is found                     int j;                     for (j = i; j >= gap && arr[j - gap] > temp; j -= gap)                         arr[j] = arr[j - gap];                       // put temp (the original a[i])                     // in its correct location                     arr[j] = temp;                 }             }             return 0;         }           /// <summary>         ///  11 Linear Search线性搜索         /// </summary>         /// <param name="arr"></param>         /// <param name="N"></param>         /// <param name="x"></param>         /// <returns></returns>         public static int LinearSearch(int[] arr, int N, int x)         {             for (int i = 0; i < N; i++)             {                 if (arr[i] == x)                     return i;             }             return -1;         }           /// <summary>         /// 12 Binary Search  二分查找         /// </summary>         /// <param name="arr"></param>         /// <param name="x"></param>         /// <returns></returns>         public static int binarySearch(int[] arr, int x)         {             int low = 0, high = arr.Length - 1;             while (low <= high)             {                 int mid = low + (high - low) / 2;                   // Check if x is present at mid                 if (arr[mid] == x)                     return mid;                   // If x greater, ignore left half                 if (arr[mid] < x)                     low = mid + 1;                   // If x is smaller, ignore right half                 else                     high = mid - 1;             }               // If we reach here, then element was             // not present             return -1;         }           static int bingo;         static int nextBingo;           // Function for finding the maximum and minimum element         // of         // the Array         /// <summary>         ///         /// </summary>         /// <param name="vec"></param>         /// <param name="n"></param>         static void maxMin(int[] vec, int n)         {             for (int i = 1; i < n; i++)             {                 bingo = Math.Min(bingo, vec[i]);                 nextBingo = Math.Max(nextBingo, vec[i]);             }         }           // Function to sort the array         /// <summary>         /// 13 Bingo Sort宾果排序         /// </summary>         /// <param name="vec"></param>         /// <param name="n"></param>         /// <returns></returns>          public  static int[] bingoSort(int[] vec, int n)         {             bingo = vec[0];             nextBingo = vec[0];             maxMin(vec, n);             int largestEle = nextBingo;             int nextElePos = 0;             while (bingo < nextBingo)             {                 // Will keep the track of the element position                 // to                 // shifted to their correct position                 int startPos = nextElePos;                 for (int i = startPos; i < n; i++)                 {                     if (vec[i] == bingo)                     {                         int temp = vec[i];                         vec[i] = vec[nextElePos];                         vec[nextElePos] = temp;                         nextElePos = nextElePos + 1;                     }                     // Here we are finding the next Bingo                     // Element for the next pass                     else if (vec[i] < nextBingo)                         nextBingo = vec[i];                 }                 bingo = nextBingo;                 nextBingo = largestEle;             }             return vec;         }             const int RUN = 32;           // This function sorts array from left         // index to to right index which is         // of size atmost RUN         private static void insertionSort(int[] arr, int left, int right)         {             for (int i = left + 1; i <= right; i++)             {                 int temp = arr[i];                 int j = i - 1;                 while (j >= left && arr[j] > temp)                 {                     arr[j + 1] = arr[j];                     j--;                 }                 arr[j + 1] = temp;             }         }           // Merge function merges the sorted runs         /// <summary>         /// 14 Tim Sort         /// </summary>         /// <param name="arr"></param>         /// <param name="l"></param>         /// <param name="m"></param>         /// <param name="r"></param>         private static void timMerge(int[] arr, int l, int m, int r)         {               // original array is broken in two parts             // left and right array             int len1 = m - l + 1, len2 = r - m;             int[] left = new int[len1];             int[] right = new int[len2];             for (int x = 0; x < len1; x++)                 left[x] = arr[l + x];             for (int x = 0; x < len2; x++)                 right[x] = arr[m + 1 + x];               int i = 0;             int j = 0;             int k = l;               // After comparing, we merge those two array             // in larger sub array             while (i < len1 && j < len2)             {                 if (left[i] <= right[j])                 {                     arr[k] = left[i];                     i++;                 }                 else                 {                     arr[k] = right[j];                     j++;                 }                 k++;             }               // Copy remaining elements             // of left, if any             while (i < len1)             {                 arr[k] = left[i];                 k++;                 i++;             }               // Copy remaining element             // of right, if any             while (j < len2)             {                 arr[k] = right[j];                 k++;                 j++;             }         }           // Iterative Timsort function to sort the         // array[0...n-1] (similar to merge sort)         void timSort(int[] arr, int n)         {               // Sort individual subarrays of size RUN             for (int i = 0; i < n; i += RUN)                 insertionSort(arr, i, Math.Min((i + RUN - 1), (n - 1)));               // Start merging from size RUN (or 32).             // It will merge             // to form size 64, then 128, 256             // and so on ....             for (int size = RUN; size < n; size = 2 * size)             {                   // pick starting point of                 // left sub array. We                 // are going to merge                 // arr[left..left+size-1]                 // and arr[left+size, left+2*size-1]                 // After every merge, we                 // increase left by 2*size                 for (int left = 0; left < n; left += 2 * size)                 {                       // Find ending point of                     // left sub array                     // mid+1 is starting point                     // of right sub array                     int mid = left + size - 1;                     int right = Math.Min((left + 2 * size - 1), (n - 1));                       // merge sub array arr[left.....mid] &                     // arr[mid+1....right]                     if (mid < right)                         timMerge(arr, left, mid, right);                 }             }         }             // To find gap between elements         /// <summary>         ///         /// </summary>         /// <param name="gap"></param>         /// <returns></returns>          private  static int getNextGap(int gap)         {             // Shrink gap by Shrink factor             gap = (gap * 10) / 13;             if (gap < 1)                 return 1;             return gap;         }           // Function to sort arr[] using Comb Sort         /// <summary>         ///  15  Comb Sort         /// </summary>         /// <param name="arr"></param>         public static void CombSort(int[] arr)         {             int n = arr.Length;               // initialize gap             int gap = n;               // Initialize swapped as true to             // make sure that loop runs             bool swapped = true;               // Keep running while gap is more than             // 1 and last iteration caused a swap             while (gap != 1 || swapped == true)             {                 // Find next gap                 gap = getNextGap(gap);                   // Initialize swapped as false so that we can                 // check if swap happened or not                 swapped = false;                   // Compare all elements with current gap                 for (int i = 0; i < n - gap; i++)                 {                     if (arr[i] > arr[i + gap])                     {                         // Swap arr[i] and arr[i+gap]                         int temp = arr[i];                         arr[i] = arr[i + gap];                         arr[i + gap] = temp;                           // Set swapped                         swapped = true;                     }                 }             }         }           /// <summary>         /// 16  Pigeonhole Sort 鸽巢排序         /// </summary>         /// <param name="arr"></param>         /// <param name="n"></param>         public static void pigeonholeSort(int[] arr, int n)         {             int min = arr[0];             int max = arr[0];             int range, i, j, index;               for (int a = 0; a < n; a++)             {                 if (arr[a] > max)                     max = arr[a];                 if (arr[a] < min)                     min = arr[a];             }               range = max - min + 1;             int[] phole = new int[range];               for (i = 0; i < n; i++)                 phole[i] = 0;               for (i = 0; i < n; i++)                 phole[arr[i] - min]++;                 index = 0;               for (j = 0; j < range; j++)                 while (phole[j]-- > 0)                     arr[index++] = j + min;           }         /// <summary>         /// 17 Cycle Sort 循环排序         /// </summary>         /// <param name="arr"></param>         /// <param name="n"></param>         public static void CycleSort(int[] arr, int n)         {             int i = 0;             while (i < n)             {                 // as array is of 1 based indexing so the                 // correct position or index number of each                 // element is element-1 i.e. 1 will be at 0th                 // index similarly 2 correct index will 1 so                 // on...                 int correctpos = arr[i] - 1;                 if (arr[i] < n && arr[i] != arr[correctpos])                 {                     // if array element should be lesser than                     // size and array element should not be at                     // its correct position then only swap with                     // its correct position or index value                     CycleSwap(arr, i, correctpos);                 }                 else                 {                     // if element is at its correct position                     // just increment i and check for remaining                     // array elements                     i++;                 }             }             Console.Write("\nAfter sort : ");             for (int index = 0; index < n; index++)                 Console.Write(arr[index] + " ");         }         /// <summary>         ///         /// </summary>         /// <param name="arr"></param>         /// <param name="i"></param>         /// <param name="correctpos"></param>         private static void CycleSwap(int[] arr, int i, int correctpos)         {             // swap elements with their correct indexes             int temp = arr[i];             arr[i] = arr[correctpos];             arr[correctpos] = temp;         }           /// <summary>         /// 18 Cocktail Sort 鸡尾酒排序         /// </summary>         /// <param name="arr"></param>         public static void cocktailSort(List<int> arr)         {             int n = arr.Count;             bool swapped = true;             int start = 0;             int end = n - 1;             while (swapped)             {                 // Move from left to right                 swapped = false;                 for (int i = start; i < end; i++)                 {                     if (arr[i] > arr[i + 1])                     {                         cocktailSwap(arr, i, i + 1);                         swapped = true;                     }                 }                 if (!swapped)                 {                     break;                 }                 end--;                 // Move from right to left                 swapped = false;                 for (int i = end - 1; i >= start; i--)                 {                     if (arr[i] > arr[i + 1])                     {                         cocktailSwap(arr, i, i + 1);                         swapped = true;                     }                 }                 start++;             }         }         /// <summary>         ///         /// </summary>         /// <param name="arr"></param>         /// <param name="i"></param>         /// <param name="j"></param>         private static void cocktailSwap(List<int> arr, int i, int j)         {             int temp = arr[i];             arr[i] = arr[j];             arr[j] = temp;         }             // Define a helper function to merge two sorted lists         /// <summary>         ///         /// </summary>         /// <param name="list1"></param>         /// <param name="list2"></param>         /// <returns></returns>         private static List<int> MergeLists(List<int> list1, List<int> list2)         {             List<int> result = new List<int>();             while (list1.Count > 0 && list2.Count > 0)             {                 if (list1[0] < list2[0])                 {                     result.Add(list1[0]);                     list1.RemoveAt(0);                 }                 else                 {                     result.Add(list2[0]);                     list2.RemoveAt(0);                 }             }             result.AddRange(list1);             result.AddRange(list2);             return result;         }           // Recursive function to perform strand sort         /// <summary>         /// 19 Strand Sort 经典排序         /// </summary>         /// <param name="inputList"></param>         /// <returns></returns>         public static List<int> PerformStrandSort(List<int> inputList)         {             // Base case: if the input list has 1 or fewer elements, it's already sorted             if (inputList.Count <= 1)             {                 return inputList;             }               // Initialize a sublist with the first element of the input list             List<int> sublist = new List<int>();             sublist.Add(inputList[0]);             inputList.RemoveAt(0);               int i = 0;             while (i < inputList.Count)             {                 // If the current element in the input list is greater than the last element in the sublist,                 // add it to the sublist; otherwise, continue to the next element in the input list.                 if (inputList[i] > sublist[sublist.Count - 1])                 {                     sublist.Add(inputList[i]);                     inputList.RemoveAt(i);                 }                 else                 {                     i++;                 }             }               // The sortedSublist contains the sorted elements from the current sublist             List<int> sortedSublist = new List<int>(sublist);               // Recursively sort the remaining part of the input list             List<int> remainingList = PerformStrandSort(inputList);               // Merge the sorted sublist and the sorted remainingList             return MergeLists(sortedSublist, remainingList);         }             /* To swap values */         /// <summary>         ///         /// </summary>         /// <typeparam name="T"></typeparam>         /// <param name="lhs"></param>         /// <param name="rhs"></param>         private static void bitonicSwap<T>(ref T lhs, ref T rhs)         {             T temp;             temp = lhs;             lhs = rhs;             rhs = temp;         }         /// <summary>         ///         /// </summary>         /// <param name="a"></param>         /// <param name="i"></param>         /// <param name="j"></param>         /// <param name="dir"></param>         private static void compAndSwap(int[] a, int i, int j, int dir)         {             int k;             if ((a[i] > a[j]))                 k = 1;             else                 k = 0;             if (dir == k)                 bitonicSwap(ref a[i], ref a[j]);         }           /*It recursively sorts a bitonic sequence in ascending order,           if dir = 1, and in descending order otherwise (means dir=0).           The sequence to be sorted starts at index position low,           the parameter cnt is the number of elements to be sorted.*/         /// <summary>         ///         /// </summary>         /// <param name="a"></param>         /// <param name="low"></param>         /// <param name="cnt"></param>         /// <param name="dir"></param>         private static void bitonicMerge(int[] a, int low, int cnt, int dir)         {             if (cnt > 1)             {                 int k = cnt / 2;                 for (int i = low; i < low + k; i++)                     compAndSwap(a, i, i + k, dir);                 bitonicMerge(a, low, k, dir);                 bitonicMerge(a, low + k, k, dir);             }         }           /* This function first produces a bitonic sequence by recursively             sorting its two halves in opposite sorting orders, and then             calls bitonicMerge to make them in the same order */         /// <summary>         ///         /// </summary>         /// <param name="a"></param>         /// <param name="low"></param>         /// <param name="cnt"></param>         /// <param name="dir"></param>         private static void bitonicSort(int[] a, int low, int cnt, int dir)         {             if (cnt > 1)             {                 int k = cnt / 2;                   // sort in ascending order since dir here is 1                 bitonicSort(a, low, k, 1);                   // sort in descending order since dir here is 0                 bitonicSort(a, low + k, k, 0);                   // Will merge whole sequence in ascending order                 // since dir=1.                 bitonicMerge(a, low, cnt, dir);             }         }           /* Caller of bitonicSort for sorting the entire array of            length N in ASCENDING order */         /// <summary>         /// 20  Bitonic Sort 双调排序         /// </summary>         /// <param name="a"></param>         /// <param name="N"></param>         /// <param name="up"></param>         public static void BitonicSort(int[] a, int N, int up)         {             bitonicSort(a, 0, N, up);         }           // Reverses arr[0..i]         /// <summary>         ///         /// </summary>         /// <param name="arr"></param>         /// <param name="i"></param>         private static void PancakeFlip(int[] arr, int i)         {             int temp, start = 0;             while (start < i)             {                 temp = arr[start];                 arr[start] = arr[i];                 arr[i] = temp;                 start++;                 i--;             }         }           // Recursive function to sort the array using pancake         // sort         /// <summary>         /// 21 Pancake Sort 煎饼排序.         /// </summary>         /// <param name="arr"></param>         /// <param name="n"></param>         public static void PancakeSort(int[] arr, int n)         {             // Base case: If the array is already sorted or has             // only one element, return             if (n == 1)                 return;               // Find the index of the maximum element in the             // unsorted portion of the array             int mi = 0;             for (int i = 0; i < n; i++)             {                 if (arr[i] > arr[mi])                 {                     mi = i;                 }             }               // Move the maximum element to the front of the             // array if it's not already there             if (mi != 0)             {                 PancakeFlip(arr, mi);             }               // Flip the entire array to move the maximum element             // to its correct position             PancakeFlip(arr, n - 1);               // Recursively sort the remaining unsorted portion             // of the array             PancakeSort(arr, n - 1);         }           // To Swap two given numbers         /// <summary>         ///         /// </summary>         /// <typeparam name="T"></typeparam>         /// <param name="lhs"></param>         /// <param name="rhs"></param>          private  static void bogoSwap<T>(ref T lhs, ref T rhs)         {             T temp;             temp = lhs;             lhs = rhs;             rhs = temp;         }           // To check if array is sorted or not         /// <summary>         ///         /// </summary>         /// <param name="a"></param>         /// <param name="n"></param>         /// <returns></returns>         private static bool isSorted(int[] a, int n)         {             int i = 0;             while (i < n - 1)             {                 if (a[i] > a[i + 1])                     return false;                 i++;             }             return true;         }           // To generate permutation of the array         /// <summary>         ///         /// </summary>         /// <param name="a"></param>         /// <param name="n"></param>         private static void bogoShuffle(int[] a, int n)         {             Random rnd = new Random();             for (int i = 0; i < n; i++)                 bogoSwap(ref a[i], ref a[rnd.Next(0, n)]);         }           // Sorts array a[0..n-1] using Bogo sort         /// <summary>         /// 22 Bogo Sort  BogoSort or Permutation Sort 置换排序、愚蠢排序、慢排序、猎枪排序或猴子排序         /// </summary>         /// <param name="a"></param>         /// <param name="n"></param>         public static void bogoSort(int[] a, int n)         {             // if array is not sorted then shuffle             // the array again             while (!isSorted(a, n))                 bogoShuffle(a, n);         }         /// <summary>         /// 23 Gnome Sort 地精排序,也称侏儒排序         /// </summary>         /// <param name="arr"></param>         /// <param name="n"></param>         public static void gnomeSort(int[] arr, int n)         {             int index = 0;               while (index < n)             {                 if (index == 0)                     index++;                 if (arr[index] >= arr[index - 1])                     index++;                 else                 {                     int temp = 0;                     temp = arr[index];                     arr[index] = arr[index - 1];                     arr[index - 1] = temp;                     index--;                 }             }             return;         }             // This function will be executed by each thread         /// <summary>         ///         /// </summary>         /// <param name="num"></param>         private static void Routine(int num)         {             // Sleeping time is proportional to the number             Thread.Sleep(num);  // Sleep for 'num' milliseconds             Console.Write(num + " ");         }           // A function that performs sleep sort         /// <summary>         /// 24.Sleep Sort 睡眠排序  The King of Laziness / Sorting while Sleeping         /// </summary>         /// <param name="arr"></param>         public static void SleepSort(List<int> arr)         {             List<Thread> threads = new List<Thread>();               // Create a thread for each element in the input array             foreach (int num in arr)             {                 Thread thread = new Thread(() => Routine(num));                 threads.Add(thread);                 thread.Start();             }               // Wait for all threads to finish             foreach (Thread thread in threads)             {                 thread.Join();             }         }           // Function to implement stooge sort         /// <summary>         /// 25 Stooge Sort 臭皮匠排序         /// </summary>         /// <param name="arr"></param>         /// <param name="l"></param>         /// <param name="h"></param>         public static void stoogeSort(int[] arr,int l, int h)         {             if (l >= h)                 return;               // If first element is smaller             // than last, swap them             if (arr[l] > arr[h])             {                 int t = arr[l];                 arr[l] = arr[h];                 arr[h] = t;             }               // If there are more than 2              // elements in the array             if (h - l + 1 > 2)             {                 int t = (h - l + 1) / 3;                   // Recursively sort first                  // 2/3 elements                 stoogeSort(arr, l, h - t);                   // Recursively sort last                 // 2/3 elements                 stoogeSort(arr, l + t, h);                   // Recursively sort first                  // 2/3 elements again to                  // confirm                 stoogeSort(arr, l, h - t);             }         }           // Modifying tag array so that we can access         // persons in sorted order of salary.         /// <summary>         /// 26 Tag Sort (To get both sorted and original)         /// </summary>         /// <param name="persons"></param>         /// <param name="tag"></param>         public static void TagSort(Person[] persons, int[] tag)         {             int n = persons.Length;             for (int i = 0; i < n; i++)             {                 for (int j = i + 1; j < n; j++)                 {                     if (persons[tag[i]].GetSalary() >                             persons[tag[j]].GetSalary())                     {                         // Note we are not sorting the                         // actual Persons array, but only                         // the tag array                         int temp = tag[i];                         tag[i] = tag[j];                         tag[j] = temp;                     }                 }             }         }            // static TreeNode root = null;         // This method mainly         // calls insertRec()         static void insert(TreeNode root,int key)         {             root = insertRec(root, key);         }           /* A recursive function to            insert a new key in BST */         /// <summary>         ///         /// </summary>         /// <param name="root"></param>         /// <param name="key"></param>         /// <returns></returns>         static  TreeNode insertRec(TreeNode root, int key)         {               /* If the tree is empty,                 return a new node */             if (root == null)             {                 root = new TreeNode(key);                 return root;             }               /* Otherwise, recur                 down the tree */             if (key < root.key)                 root.left = insertRec(root.left, key);             else if (key > root.key)                 root.right = insertRec(root.right, key);               /* return the root */             return root;         }           // A function to do          // inorder traversal of BST         /// <summary>         ///         /// </summary>         /// <param name="root"></param>         public static void inorderRec(TreeNode root)         {             if (root != null)             {                 inorderRec(root.left);                 Console.Write(root.key + " ");                 inorderRec(root.right);             }         }         /// <summary>         /// 27 Tree Sort         /// </summary>         /// <param name="arr"></param>         /// <param name="root"></param>         public static void treeins(int[] arr, TreeNode root)         {             for (int i = 0; i < arr.Length; i++)             {                 insert(root,arr[i]);             }           }         /// <summary>         /// 28.Brick Sort / Odd-Even Sort 砖排序算法（Brick Sort），也被称为奇偶排序（Odd-Even Sort）         /// </summary>         /// <param name="arr"></param>         /// <param name="n"></param>         public static void BrickSort(int[] arr, int n)         {             // Initially array is unsorted             bool isSorted = false;               while (!isSorted)             {                 isSorted = true;                 int temp = 0;                   // Perform Bubble sort on                 // odd indexed element                 for (int i = 1; i <= n - 2; i = i + 2)                 {                     if (arr[i] > arr[i + 1])                     {                         temp = arr[i];                         arr[i] = arr[i + 1];                         arr[i + 1] = temp;                         isSorted = false;                     }                 }                   // Perform Bubble sort on                 // even indexed element                 for (int i = 0; i <= n - 2; i = i + 2)                 {                     if (arr[i] > arr[i + 1])                     {                         temp = arr[i];                         arr[i] = arr[i + 1];                         arr[i + 1] = temp;                         isSorted = false;                     }                 }             }             return;         }             // Function  for 3-way merge sort process         /// <summary>         ///  29. 3-way Merge Sort 3路归并排序         /// </summary>         /// <param name="gArray"></param>         public static void mergeSort3Way(int[] gArray)         {             // if array of size is zero returns null             if (gArray == null)                 return;               // creating duplicate of given array             int[] fArray = new int[gArray.Length];               // copying elements of given array into             // duplicate array             for (int i = 0; i < fArray.Length; i++)                 fArray[i] = gArray[i];               // sort function             mergeSort3WayRec(fArray, 0, gArray.Length, gArray);               // copy back elements of duplicate array             // to given array             for (int i = 0; i < fArray.Length; i++)                 gArray[i] = fArray[i];         }           /* Performing the merge sort algorithm on the              given array of values in the rangeof indices              [low, high).  low is minimum index, high is              maximum index (exclusive) */         /// <summary>         ///         /// </summary>         /// <param name="gArray"></param>         /// <param name="low"></param>         /// <param name="high"></param>         /// <param name="destArray"></param>         private static void mergeSort3WayRec(int[] gArray,int low, int high, int[] destArray)         {             // If array size is 1 then do nothing             if (high - low < 2)                 return;               // Splitting array into 3 parts             int mid1 = low + ((high - low) / 3);             int mid2 = low + 2 * ((high - low) / 3) + 1;               // Sorting 3 arrays recursively             mergeSort3WayRec(destArray, low, mid1, gArray);             mergeSort3WayRec(destArray, mid1, mid2, gArray);             mergeSort3WayRec(destArray, mid2, high, gArray);               // Merging the sorted arrays             WayMerge(destArray, low, mid1, mid2, high, gArray);         }           /* Merge the sorted ranges [low, mid1), [mid1,              mid2) and [mid2, high) mid1 is first midpoint              index in overall range to merge mid2 is second              midpoint index in overall range to merge*/         /// <summary>         ///         /// </summary>         /// <param name="gArray"></param>         /// <param name="low"></param>         /// <param name="mid1"></param>         /// <param name="mid2"></param>         /// <param name="high"></param>         /// <param name="destArray"></param>         private static void WayMerge(int[] gArray, int low,int mid1, int mid2, int high,int[] destArray)         {             int i = low, j = mid1, k = mid2, l = low;               // choose smaller of the smallest in the three ranges             while ((i < mid1) && (j < mid2) && (k < high))             {                 if (gArray[i].CompareTo(gArray[j]) < 0)                 {                     if (gArray[i].CompareTo(gArray[k]) < 0)                         destArray[l++] = gArray[i++];                       else                         destArray[l++] = gArray[k++];                 }                 else                 {                     if (gArray[j].CompareTo(gArray[k]) < 0)                         destArray[l++] = gArray[j++];                     else                         destArray[l++] = gArray[k++];                 }             }               // case where first and second ranges have             // remaining values             while ((i < mid1) && (j < mid2))             {                 if (gArray[i].CompareTo(gArray[j]) < 0)                     destArray[l++] = gArray[i++];                 else                     destArray[l++] = gArray[j++];             }               // case where second and third ranges have             // remaining values             while ((j < mid2) && (k < high))             {                 if (gArray[j].CompareTo(gArray[k]) < 0)                     destArray[l++] = gArray[j++];                   else                     destArray[l++] = gArray[k++];             }               // case where first and third ranges have             // remaining values             while ((i < mid1) && (k < high))             {                 if (gArray[i].CompareTo(gArray[k]) < 0)                     destArray[l++] = gArray[i++];                 else                     destArray[l++] = gArray[k++];             }               // copy remaining values from the first range             while (i < mid1)                 destArray[l++] = gArray[i++];               // copy remaining values from the second range             while (j < mid2)                 destArray[l++] = gArray[j++];               // copy remaining values from the third range             while (k < high)                 destArray[l++] = gArray[k++];         }           } }

　　

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/*****************************************************************//**  * \file    SortExample.cs  * \brief  csharp Sorting Algorithms 算法  * IDE  vs 2022 C#  .net 6.0  * https://www.geeksforgeeks.org/merge-sort/?ref=lbp  * \author geovindu,Geovin Du,涂聚文  * \date   September 28 2023  *********************************************************************/   using System; using SortingAlgorithms;       namespace BLL {            /// <summary>     /// 示例     /// </summary>     public class SortExample     {           /// <summary>         /// 1.Bubble Sort冒泡排序法         /// </summary>         public static void Bubble()         {             int[] geovindu = { 64, 34, 25, 12, 22, 11, 90 };             int n = geovindu.Length;               SortingAlgorithm.BubbleSort(geovindu);             Console.WriteLine("1.Bubble Sorted array:");             SortingAlgorithms.SortingAlgorithm.printArray(geovindu);           }         /// <summary>         /// 2.Selection Sort 选择排序         /// </summary>         public static void Selection()         {             int[] geovindu = { 64, 34, 25, 12, 22, 11, 90 };             int n = geovindu.Length;               SortingAlgorithm.SelectionSort(geovindu);             Console.WriteLine("2.Selection Sorted array:");             SortingAlgorithms.SortingAlgorithm.printArray(geovindu);         }         /// <summary>         /// 3. 插入排序 Insertion Sort         /// </summary>         public static void Insertion()         {             int[] geovindu = { 64, 34, 25, 12, 22, 11, 90 };             int n = geovindu.Length;               SortingAlgorithm.InsertionSort(geovindu);             Console.WriteLine("3.Insertion Sorted array:");             SortingAlgorithms.SortingAlgorithm.printArray(geovindu);         }         /// <summary>         /// 4 Quick Sort 快速排序         /// </summary>           public static void quickSort()         {             int[] arr = { 10, 7, 8, 9, 1, 5 };             int N = arr.Length;               // Function call             SortingAlgorithms.SortingAlgorithm.quickSort(arr, 0, N - 1);             Console.WriteLine("Sorted array:");             for (int i = 0; i < N; i++)                 Console.Write(arr[i] + " ");         }         /// <summary>         /// 5 Merge Sort 合并/归并排序         /// </summary>         public static void MergeSort()         {             int[] arr = { 12, 11, 13, 5, 6, 7 };             Console.WriteLine("Given array is");                         SortingAlgorithms.SortingAlgorithm.MergeSort(arr, 0, arr.Length - 1);             Console.WriteLine("\nSorted array is");             int n = arr.Length;             for (int i = 0; i < n; ++i)                 Console.Write(arr[i] + " ");             Console.WriteLine();         }           /// <summary>         /// Iterative Merge Sort for Linked List         /// </summary>         public static void LinkedMergeSort()         {             // start with empty list             Node head = null;               // create linked list             // 1.2.3.4.5.6.7             head = SortingAlgorithms.SortingAlgorithm.LinkedPush(head, 7);             head = SortingAlgorithms.SortingAlgorithm.LinkedPush(head, 6);             head = SortingAlgorithms.SortingAlgorithm.LinkedPush(head, 5);             head = SortingAlgorithms.SortingAlgorithm.LinkedPush(head, 4);             head = SortingAlgorithms.SortingAlgorithm.LinkedPush(head, 3);             head = SortingAlgorithms.SortingAlgorithm.LinkedPush(head, 2);             head = SortingAlgorithms.SortingAlgorithm.LinkedPush(head, 1);               head = SortingAlgorithms.SortingAlgorithm.LinkedMergeSort(head);               if ((head) == null)                 return;             Node temp = head;             while (temp != null)             {                 Console.Write(temp.data + " ");                 temp = temp.next;             }             Console.Write("\n");         }         /// <summary>         ///  6 Counting Sort 计数排序         /// </summary>         public static void countSort()         {               // Input array             List<int> inputArray = new List<int>();// { 4, 3, 12, 1, 5, 5, 3, 9 };             inputArray.Add(4);             inputArray.Add(3);             inputArray.Add(12);             inputArray.Add(1);             inputArray.Add(5);             inputArray.Add(5);             inputArray.Add(3);             inputArray.Add(9);               // Output array             List<int> outputArray = SortingAlgorithms.SortingAlgorithm.countSort(inputArray);             for (int i = 0; i < inputArray.Count; i++)                 Console.Write(outputArray[i] + " ");             Console.WriteLine();           }         /// <summary>         /// 7 Radix Sort 基数排序         /// </summary>         public static void radixSort()         {             int[] arr = { 170, 45, 75, 90, 802, 24, 2, 66 };             int n = arr.Length;               // Function Call             SortingAlgorithms.SortingAlgorithm.radixSort(arr, n);             for (int i = 0; i < n; i++)                 Console.Write(arr[i] + " ");               }           /// <summary>         /// 8 Bucket Sort 桶排序         /// </summary>         public static void BucketSort()         {             float[] arr = { 0.897f, 0.565f, 0.656f, 0.1234f, 0.665f, 0.3434f };             SortingAlgorithms.SortingAlgorithm.BucketSort(arr);             Console.WriteLine("Sorted array is:");             foreach (float num in arr)             {                 Console.Write(num + " ");             }         }           /// <summary>         /// 9 Heap Sort 堆排序         /// </summary>         public static void HeapSort()         {             int[] arr = { 12, 11, 13, 5, 6, 7 };             int N = arr.Length;             // Function call                       SortingAlgorithms.SortingAlgorithm.HeapSort(arr);             Console.WriteLine("Sorted array is");                    for (int i = 0; i < N; ++i)                 Console.Write(arr[i] + " ");             Console.Read();           }         /// <summary>         /// 10 Shell Sort 希尔排序         /// </summary>         public static void ShellSort()         {               int[] arr = { 12, 34, 54, 2, 3 };             Console.Write("Array before sorting :\n");                 SortingAlgorithms.SortingAlgorithm.ShellSort(arr);               Console.Write("Array after sorting :\n");             int n = arr.Length;             for (int i = 0; i < n; ++i)                 Console.Write(arr[i] + " ");             Console.WriteLine();           }           /// <summary>         /// 11 Linear Search线性搜索         /// </summary>         /// <returns></returns>         public static void LinearSearch()         {             int[] arr = { 2, 3, 4, 10, 40 };             int x = 10;               // Function call             int result = SortingAlgorithms.SortingAlgorithm.LinearSearch(arr, arr.Length, x);             if (result == -1)                 Console.WriteLine(                     "Element is not present in array");             else                 Console.WriteLine("Element is present at index "                                   + result);         }         /// <summary>         /// 12 Binary Search  二分查找         /// </summary>         public static void binarySearch()         {             int[] arr = { 2, 3, 4, 10, 40 };             int n = arr.Length;             int x = 10;             int result = SortingAlgorithms.SortingAlgorithm.binarySearch(arr, x);             if (result == -1)                 Console.WriteLine(                     "Element is not present in array");             else                 Console.WriteLine("Element is present at "                                   + "index " + result);         }         /// <summary>         /// 13 Bingo Sort宾果排序         /// </summary>           public static void bingoSort()         {             int[] arr = { 5, 4, 8, 5, 4, 8, 5, 4, 4, 4 };             arr = SortingAlgorithms.SortingAlgorithm.bingoSort(arr, arr.Length);                          int[] arr2 = { 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 };             arr2 = SortingAlgorithms.SortingAlgorithm.bingoSort(arr2, arr2.Length);                           int[] arr3 = { 0, 1, 0, 1, 0, 1 };             arr3 = SortingAlgorithms.SortingAlgorithm.bingoSort(arr3, arr3.Length);             Console.Write("Sorted Array: ");               for (int i = 0; i < arr.Length; i++)             {                 Console.Write(arr[i] + " ");             }             Console.WriteLine();         }           /// <summary>         ///         ///  15  Comb Sort         /// </summary>         public static void CombSort()         {               int[] arr = { 8, 4, 1, 56, 3, -44, 23, -6, 28, 0 };             SortingAlgorithms.SortingAlgorithm.CombSort(arr);               Console.WriteLine("sorted array");             for (int i = 0; i < arr.Length; ++i)                 Console.Write(arr[i] + " ");           }         /// <summary>         /// 16  Pigeonhole Sort 鸽巢排序         /// </summary>         public static void pigeonholeSort()         {             int[] arr = {8, 3, 2, 7,                  4, 6, 8};               Console.Write("Sorted order is : ");               SortingAlgorithms.SortingAlgorithm.pigeonholeSort(arr, arr.Length);               for (int i = 0; i < arr.Length; i++)                 Console.Write(arr[i] + " ");         }           /// <summary>         /// 17 Cycle Sort 循环排序         /// </summary>         public static void CycleSort()         {             // Code             int[] arr = { 3, 2, 4, 5, 1 };             int n = arr.Length;             Console.Write("Before sort : ");             for (int i = 0; i < n; i++)                 Console.Write(arr[i] + " ");             SortingAlgorithms.SortingAlgorithm.CycleSort(arr, n);         }         /// <summary>         /// 18 Cocktail Sort 鸡尾酒排序         /// </summary>         public static void cocktailSort()         {             List<int> arr = new List<int> { 5, 2, 9, 3, 7, 6 };             SortingAlgorithms.SortingAlgorithm.cocktailSort(arr);             foreach (var x in arr)             {                 Console.Write(x + " ");             }             Console.WriteLine();         }         /// <summary>         /// 19 Strand Sort 经典排序         /// </summary>         public static void StrandSort()         {             List<int> inputList = new List<int> { 10, 5, 30, 40, 2, 4, 9 };               List<int> outputList = SortingAlgorithms.SortingAlgorithm.PerformStrandSort(inputList);               foreach (int x in outputList)             {                 Console.Write(x + " ");             }             }         /// <summary>         /// 20  Bitonic Sort 双调排序         /// </summary>         public static void BitonicSort()         {             int[] a = { 3, 7, 4, 8, 6, 2, 1, 5 };             int N = a.Length;               int up = 1;   // means sort in ascending order             SortingAlgorithms.SortingAlgorithm.BitonicSort(a, N, up);               Console.Write("Sorted array: \n");             for (int i = 0; i < N; i++)                 Console.Write(a[i] + " ");         }         /// <summary>         /// 21 Pancake Sort 煎饼排序         /// </summary>         public static void PancakeSort()         {             int[] arr = { 23, 10, 20, 11, 12, 6, 7 };             int n = arr.Length;               SortingAlgorithms.SortingAlgorithm.PancakeSort(arr, n);               Console.Write("Sorted Array: ");             for (int i = 0; i < n; i++)             {                 Console.Write(arr[i] + " ");             }             Console.WriteLine();           }         /// <summary>         /// 22 Bogo Sort  BogoSort or Permutation Sort 置换排序、愚蠢排序、慢排序、猎枪排序或猴子排序         /// </summary>         public static void bogoSort()         {               int[] a = { 3, 2, 5, 1, 0, 4 };             int n = a.Length;             SortingAlgorithms.SortingAlgorithm.bogoSort(a, n);             Console.Write("Sorted array :\n");             for (int i = 0; i < n; i++)                 Console.Write(a[i] + " ");             Console.Write("\n");         }         /// <summary>         /// 23 Gnome Sort 地精排序,也称侏儒排序         /// </summary>         public static void gnomeSort()         {             int[] arr = { 34, 2, 10, -9 };               // Function calling             SortingAlgorithms.SortingAlgorithm.gnomeSort(arr, arr.Length);               Console.Write("Sorted sequence after applying Gnome sort: ");               for (int i = 0; i < arr.Length; i++)                 Console.Write(arr[i] + " ");         }         /// <summary>         /// 24.Sleep Sort 睡眠排序  The King of Laziness / Sorting while Sleeping         /// </summary>         public static void SleepSort()         {             List<int> arr = new List<int> { 34, 23, 122, 9 };               SortingAlgorithms.SortingAlgorithm.SleepSort(arr);           }         /// <summary>         /// 25 Stooge Sort 臭皮匠排序         /// </summary>         public static void stoogeSort()         {             int[] arr = { 2, 4, 5, 3, 1 };             int n = arr.Length;               // Calling Stooge Sort function             // to sort the array             SortingAlgorithms.SortingAlgorithm.stoogeSort(arr, 0, n - 1);               // Display the sorted array             for (int i = 0; i < n; i++)                 Console.Write(arr[i] + " ");         }         /// <summary>         /// 26 Tag Sort (To get both sorted and original)         /// </summary>         public static void TagSort()         {             // Creating objects and their original             // order (in tag array)             int n = 5;             Person[] persons = new Person[n];             persons[0] = new Person(0, 233.5f);             persons[1] = new Person(1, 23f);             persons[2] = new Person(2, 13.98f);             persons[3] = new Person(3, 143.2f);             persons[4] = new Person(4, 3f);             int[] tag = new int[n];             for (int i = 0; i < n; i++)                 tag[i] = i;               // Every Person object is tagged to             // an element in the tag array.             Console.WriteLine("Given Person and Tag ");             for (int i = 0; i < n; i++)                 Console.WriteLine(persons[i] +                                 " : Tag: " + tag[i]);               // Modifying tag array so that we can access             // persons in sorted order.             SortingAlgorithms.SortingAlgorithm.TagSort(persons, tag);               Console.WriteLine("New Tag Array after " +                             "getting sorted as per Person[] ");             for (int i = 0; i < n; i++)                 Console.WriteLine(tag[i]);               // Accessing persons in sorted (by salary)             // way using modified tag array.             for (int i = 0; i < n; i++)                 Console.WriteLine(persons[tag[i]]);         }         /// <summary>         /// 27 Tree Sort         /// </summary>         public static void TreeSort()         {             // Root of BST             TreeNode root = null;             int[] arr = { 5, 4, 7, 2, 11 };             SortingAlgorithms.SortingAlgorithm.treeins(arr, root);             SortingAlgorithms.SortingAlgorithm.inorderRec(root);           }         /// <summary>         /// 28.Brick Sort / Odd-Even Sort 砖排序算法（Brick Sort），也被称为奇偶排序（Odd-Even Sort）         /// </summary>         public static void BrickSort()         {             int[] arr = { 34, 2, 10, -9 };             int n = arr.Length;               // Function calling             SortingAlgorithms.SortingAlgorithm.BrickSort(arr, n);             for (int i = 0; i < n; i++)                 Console.Write(arr[i] + " ");               Console.WriteLine(" ");           }         /// <summary>         /// 29. 3-way Merge Sort 3路归并排序         /// </summary>         public static void mergeSort3Way()         {             // test case of values             int[] data = new int[] {45, -2, -45, 78,                             30, -42, 10, 19, 73, 93};             SortingAlgorithms.SortingAlgorithm.mergeSort3Way(data);             Console.Write("After 3 way merge sort: ");             for (int i = 0; i < data.Length; i++)                 Console.Write(data[i] + " ");           }                 }   }

　　

 

 

 

 

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/*****************************************************************//**  * \file    Program.cs  * \brief  csharp Sorting Algorithms 算法  * IDE  vs 2022 C#  .net 6.0  * \author geovindu  * \date   September 28 2023  *********************************************************************/   // See https://aka.ms/new-console-template for more information   using BLL;           Console.WriteLine("Hello, World! 涂聚文 Geovin Du,geovindu, 学习CSharp"); //1. SortExample.Bubble(); //2. SortExample.Selection(); //3. SortExample.Insertion();