#include <vector>
#include <iostream>
using namespace std;
void sort(vector<int> &v, int b0, int e0)
{
auto d = v[e0];
auto b = b0;
auto e = e0;
do
{
while (v[b] < d)
++b;
while (v[e] > d)
--e;
if (b <= e)
{
swap(v[b], v[e]);
++b;
--e;
}
} while (b <= e);
if (e > b0)
sort(v, b0, e);
if (b < e0)
sort(v, b, e0);
}
int main()
{
vector<int> v;
for (int i = 0; i < 20; ++i)
v.push_back(i);
for (size_t i = 0; i < v.size(); ++i)
swap(v[i], v[rand() % (v.size() - i) + i]);
for (auto i: v)
cout << i << " ";
cout << endl;
sort(v, 0, v.size() - 1);
for (auto i: v)
cout << i << " ";
cout << endl;
return 0;
}
