#include <iostream>
#include <ctime>
#include <random>

using namespace std;

void QuickSort(int a[],int l, int r)
{
    int i,j;
    i = l;
    j = r;

    int mid = a[(i+j)/2];

    do
    {
        while(mid > a[i]) i++;
        while(mid < a[j]) j--;

        if(i <= j)
        {
            swap(a[i],a[j]);
            i++;
            j--;
        }
    } while (i < j);

    if(i < r) QuickSort(a,i,r);
    if(j > l) QuickSort(a,l,j);
}
void PrintArr(const int a[], int n)
{
    for (int i(0); i < n; i++) {
        cout << ((i!=0) and (i%5==0)? "\n": "");
        cout << "A[" << i << "] = " << a[i]  << "  ";
    }
}

int main()
{
    const int N = 50;
    int a[N];
    srand(time(NULL));

    for(int i(0);i<N;i++)
        a[i] = rand()%100+1;

    cout << "Array before\n";
    PrintArr(a,N);

    double t1 = clock();
    QuickSort(a,0,N-1);
    double t2 = clock() - t1;

    cout << "\nArray after\n";
    PrintArr(a,N);
    cout << "\n Time to rearrange = " << t2/CLOCKS_PER_SEC << endl;
    return 0;
}