C++ nine sort specific implementation code

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Direct insertion sort

void InsertSort(int r[])
{
 int n = sizeof(r) / sizeof(r[0]);
 for(int i = 1; i < n; ++i)
 {
  for(int j = i - 1; j >= 0; --j)
  {   
   if(r[j+1] < r[j])
   {
    int s = r[j+1];
    r[j+1] = r[j];
    r[j] = s;
   }
  }
 }
}

Half insertion sort

void BinInsertSort(int r[])
{
 int n = sizeof(r) / sizeof(r[0]);
 for(int i = 1; i < n; ++i)
 {
  int s = r[i];
  int low = 0;
  int high = i - 1;
  
  while(low <= high)
  {
   int mid = (low + high) / 2; //mid The position is the number you're looking for 
   if(s < r[mid])
    high = mid - 1;
   else
    low = mid + 1;
  }
  
  for(int j = i - 1; j >= high + 1; --j) //high+1 namely mid , the number of executions moved back until mid The number of ward 
   r[j+1] = r[j];
  
  r[high+1] = s; //mid The location is itself 
 }
}

Hill sorting

void ShellSort(int r[])
{
 int n = sizeof(r) / sizeof(r[0]);
 int step = n / 2;
 
 while(step >= 1)
 {
  for(int i = step; i < n; ++i)
  {
   for(int j = i - step; j >= 0; j -= step)
   {    
    if(r[j+step] < r[j])
    {
     int s = r[j+step];
     r[j+step] = r[j];
     r[j] = s;
    }
   }
  }
  step /= 2;
 }
}

Direct selection sort

void SelectSort(int r[])
{
 int n = sizeof(r) / sizeof(r[0]);
 for(int i = 0; i < n - 1; ++i)
 {
  int samll = i;
  for(int j = i + 1; j < n; ++j)
  {
   if(r[small] > r[j])
    samll = j;
  }
  if(small != i)
  {
   int s = r[i];
   r[i] = r[small];
   r[small] = s;
  }
 }
}

Heap sort

void HeapAdjust(int r[]; int i; int j) // Adjust the heap 
{
 int child = 2 * i;
 int s = r[i]; //s Temporary storage of node data 
 while(child <= j)
 {
  if(child < j && r[child+1] > r[child]) // To compare 2 Is the tree 
   ++child;
  if(s >= r[child]) // Nodes compared to large subtrees 
   break;
  r[child/2] = r[child]; // If the big subtree is bigger than the node, interchange 
  child = 2 * child; // Continue to retrieve to the subtree 
 }
 r[child/2] = s; // The number of nodes is the largest number 
}

void HeapSort(int r[]) // Building the heap 
{
 int n = sizeof(r) / sizeof(r[0]);
 for(int i = n / 2 - 1; i >= 0; --i) // only n/2-1 It's the subtree that has the index before it 
 {
  HeapAdjust(r, i, n - 1); // Big top heap is constructed, the nodes are all larger than the subtree, and the last root node is the largest number 
 }
 for(int i = n - 1; i > 0; --i)
 {
  // Interchanges the current top heap element with the current tail element, moving the largest number to the end 
  int s = r[0];
  r[0] = r[i];
  r[i] = s;
  HeapAdjust(r, 0, i -1); // Adjust the remaining elements until you get from small to large 
 }
}

Bubble sort

void BubbleSort(int r[])
{
 int n = sizeof(r) / sizeof(r[0]);
 for(int i = 0; i < n - 1; ++i)
 {
  for(int j = 0; j < n - 1 - i; ++j)
  {
   if(r[j] > r[j+1])
   {
    int s = r[j];
    r[j] = r[j+1];
    r[j+1] = s;
   }
  }
 }
}

Quick sort

int Partition(int r[], int low, int high)
{
 int pivotkey = r[low];
 int i = low;
 int j = high;
 
 while(i < j)
 {
  while(i < j && r[j] > pivotkey) // from j Go ahead and find the number one 1 than pivotkey A small number of 
   --j;
  if(i < j)
  {
   r[i] = r[j];
   ++i;
  }
  
  while(i < j && r[i] < pivotkey) // from i Go back and find the number one 1 than pivotkey A large number of 
   ++i;
  if(i < j)
  {
   r[j] = r[i];
   --j;
  }
 }
 r[j] = pivotkey; // Complete the final exchange 
 return j; // Returns the cut-off point, the ratio of the previous Numbers pivotkey It's smaller than everything else pivokey big 
}

void QuickSort(int r[], int low, int high) //  The array, 0 And the length of the -1
{
 if(low < high)
 {
  int pivot = Partition(r, low, high);
  QuickSort(r, low, pivot - 1); // Recursion, the first half of this is quicksort 
  QuickSort(r, pivot + 1; high); // Recursion, the second half of the quicksort continues 
 }
}

Merge sort

void copyArray(int source[], int dest[], int len, int first)
{
  int i;
  int j = first;
  for(i = 0; i < len; ++i)
  {
    dest[j] = source[i];
    ++j;
  }
}

void merge(int a[], int left, int right)
{
  int begin1 = left;
  int mid = (left + right) / 2;
  int begin2 = mid + 1;
  int newArrayLen = right - left + 1;
  int *b = (int*)malloc(newArrayLen * sizeof(int));
  int k = 0;
  
  while(begin1 <= mid && begin2 <= right) // To find out 2 The smaller number in the group is put in order b space 
  {
    if(a[begin1] <= a[begin2])
      b[k++] = a[begin1++];
    else
      b[k++] = a[begin2++];
  }
  
  // Put the rest in b space 
  while(begin1 <= mid)
    b[k++] = a[begin1++];
  while(begin2 <= right)
    b[k++] = a[begin2++];
  
  copyArray(b, a, newArrayLen, left); // the b The number of Spaces is written back to the original array 
  free(b);
}

void MergeSort(int r[], int left, int right) // The array, 0 And the length of the -1
{
  int i;
  // At least two elements are sorted 
  if(left < right)
  {
    i = (left + right) / 2;
    MergeSort(r, left, i); // The first half is recursion 
    MergeSort(r, i + 1, right); // The second half is recursion     
    merge(r, left, right); //10 The order of comparison of Numbers is [0,1][0,2][3,4][0,4][5,6][5,7][8,9][5,9][0,9]
  }
}

Bucket sort

void insert(list<int> &bucket, int val)
{
  auto iter = bucket.begin();
  while(iter != bucket.end() && val >= *iter)
    ++iter;
  //insert Will be in iter I'm going to insert the data before, so that the sort is stable 
  bucket.insert(iter, val);
}

void BuckdeSort(vector<int> &arr)
{
  int len = arr.size();
  if(len <= 1)
    return;
  int min = arr[0], max = min;
  for(int i = 1; i < len; ++i) // Find the minimum and maximum 
  {
    if(min > arr[i])
      min = arr[i];
    if(max < arr[i])
      max = arr[i];
  }
  
  int k = 10; // The size of the barrel 
  
  // Round up, for example [0,9] There are 10 The number, we have theta (9-0)/k+1=1 A barrel 
  int bucketsNum = (max - min) / k + 1; // The number of barrels 
  
  vector<list<int>> buckets(bucketsNum);
  for(int i = 0; i < len; ++i)
  {
    int value = arr[i];
    //(value-min)/k It's in that bucket 
    insert(buckets[(value-min)/k], value); // Put the data into buckets and sort them 
  }
  
  int index = 0;
  for(int i = 0; i < bucketsNum; ++i)
  {
    if(buckets[i].size())
    {
      for(auto &value : buckets[i])
        arr[index++] = value;
    }
  }
}