Quick_sort.cpp

// Quick sort in C++

#include <iostream>
using namespace std;

void swap(int *a, int *b) 
{
  int t = *a;
  *a = *b;
  *b = t;
}


void printArray(int array[], int size)
{
  int i;
  for (i = 0; i < size; i++)
    cout << array[i] << " ";
  cout << endl;
}


int partition(int array[], int low, int high) 
{
  
  int pivot = array[high];
  int i = (low - 1);
  for (int j = low; j < high; j++) 
  {
    if (array[j] <= pivot) 
    {
      i++;
      swap(&array[i], &array[j]);
    }
  }
  printArray(array, 7);
  cout << "........\n";
  swap(&array[i + 1], &array[high]);
  return (i + 1);
}

void quickSort(int array[], int low, int high)
{
  if (low < high) 
  {
    int pi = partition(array, low, high);
    quickSort(array, low, pi - 1);
    quickSort(array, pi + 1, high);
  }
}


int main() 
{
  int data[] = {8, 7, 6, 1, 0, 9, 2};
  int n = sizeof(data) / sizeof(data[0]);
  quickSort(data, 0, n - 1);
  cout << "Sorted array in ascending order: \n";
  printArray(data, n);
}