#include "bits/stdc++.h"
using namespace std;

bool left_side(pair<int, int> &a, pair<int, int> &b, pair<int, int> &x) {
    return (b.first - a.first)*(x.second - a.second) - (b.second - a.second) * (x.first - a.first) >= 0;
}


vector<pair<pair<int, int>, pair<int, int>>> slow_convex_hull(vector<pair<int, int>> &input) {
    vector<pair<pair<int, int>, pair<int, int>>> output;
    for (int i{}; i < input.size(); i++) {
        for (int j = i +1; j < input.size(); j++) {
            bool valid = true;
            for (int k{}; k < input.size(); k++) {
                if (left_side(input[i], input[j], input[k])) {
                    valid = false;
                }
            }
            if (valid) {
                output.emplace_back(input[i], input[j]);
            }
        }
    }
    return output;
}

int main() {
    cout << "test";
}