Quick Sort in non-increasing order. - C++

#include <iostream>
using namespace std;

int Partition(int a[], int low, int high)
{
  int pivot = a[low];
  int i = low; 
  int j = high;
  
  while(i < j)
  {
    while(a[i] >= pivot && i <= high - 1)
      ++i;
      
    while(a[j] < pivot && j >= low + 1)
      --j;
      
    if(i < j)
      swap(a[i], a[j]);
  }
  
  swap(a[low], a[j]);
  return j;
}

void QuickSort(int a[], int low, int high)
{
  if(low < high)
  {
    int pivotIndex = Partition(a, low, high);
    
    QuickSort(a, low, pivotIndex - 1);
    QuickSort(a, pivotIndex + 1, high);
  }
}

int main() 
{
  int n;
  cin >> n;
  
  int a[n];
  for(int i = 0; i < n; ++i)
    cin >> a[i];
    
  QuickSort(a, 0, n-1);
  
  for(int i = 0; i < n; ++i)
    cout << a[i] << " ";
  
  return 0;
}