#include <iostream>
using namespace std;

int low(int a, int b){
    if (a < b){
        return 1;
    } else if (a > b){
        return -1;
    } else {
        return 0;
    }
}

void quicksort(int* arr, int c){
    int l = c; int k = 0;
    int midle = arr[c/2];
    while (k <= c){
        while (low(arr[k], arr[midle]) == 1)
            k++;

        while (low(arr[c], arr[midle]) == -1)
            c--;

        if (k <= c){
            swap(arr[k++], arr[c--]);

        }
    }



    if (c > 0)
        quicksort(arr, c);

    if (l > k)
        quicksort(arr + k, l - k);


}


int main() {

    int arr[20] = {6, 5, 4, 4, 2, 1, 3, 1, 23, 1, 2, 4, 32, 54, 45, 22, 7, 46, 99, 47};
    for(int i = 0; i < 20; i++){
        cout << arr[i] << " ";
    } cout << endl;
    quicksort(arr, 19);
    for(int i = 0; i < 20; i++){
        cout << arr[i] << " ";
    }
    return 0;
}