#ifndef QUICKSORT
#define QUICKSORT

#include <iostream>
#include <vector>
#include <algorithm>

template <typename T> 
int Partition(std::vector<T> & ary, int & low, int & high) {
    T pivot{ary[(high+low)/2]};

    int i{low-1},
        j{high+1};

    while (i < j) {
        do  {
            i++;
        } while  (ary[i] < pivot) ;

        do {
           j--;
        } while (ary[j] > pivot);

        if (i <  j) {
            std::swap(ary[i], ary[j]);
        }

    }
    return j;
}

template <typename T> 
void QuickSort(std::vector<T> & ary, int low=0, int high=-1) {
    
     if (high == -1) {
         high = static_cast<int>(ary.size())-1;
     }

     if (low >=0 and high >= 0 and low < high) {
         int pos = Partition(ary, low, high);
         QuickSort(ary, low, pos);
         QuickSort(ary, pos+1, high);
     }
}

#endif