algorithms/quick sort.cpp at master · dekzz/algorithms · GitHub

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#include <iostream>
using namespace std;

void qSort(int num[], int left, int right)
{
     int pivot, l_hold, r_hold;

     l_hold = left;
     r_hold = right;
     pivot = num[left];
     while(left < right)
     {
         while((num[right] >= pivot) && (left < right))
             right--;

         if(left != right)
         {
              num[left] = num[right];
              left++;
         }

         while((num[left] <= pivot) && (left < right))
              left++;

         if(left != right)
         {
               num[right] = num[left];
               right--;
         }
     }

     num[left] = pivot;
     pivot = left;
     left = l_hold;
     right = l_hold;

     if (left < pivot)
        qSort(num, left, pivot-1);

     if (right > pivot)
        qSort(num, pivot+1, right);
}

void quickSort(int num[], int size)
{
     qSort(num, 0, size-1);
}

int main()
{
    int N;
    cout << "Number of elements: ";
    cin >> N;
    int array[N];

    cout << "Enter the elements: " << endl;
    for(int i = 0; i < N; i++)
    {
            cin >> array[i];
    }

    quickSort(array, N);

    cout << "Sorted: " << endl;
    for(int i = 0; i < N; i++)
            cout << array[i] << endl;

    system("pause");
    return 0;
}