#define _CRT_SECURE_NO_WARNINGS
#include "bits/stdc++.h"
//#include "geometry.h"
//#include "data_structure.h"
using namespace std;
using namespace chrono;
#define all(a) a.begin(), a.end()
#define allr(a) a.rbegin(), a.rend()
mt19937 rnd(std::chrono::high_resolution_clock::now().time_since_epoch().count());
typedef long long ll;
typedef double ld;
signed main() {
#ifdef _DEBUG
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    srand(time(NULL));
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    ll n = 1e5;
    ll k = 1e4;
    vector<ll> a(n);
    for (ll i = 0; i < n; i++) {
        cin >> a[i];
    }
    sort(all(a));
    struct My{
        ll cnt = 0;
        ll start = 0;
        ll ind = 0;
    };
    a.resize(unique(all(a)) - a.begin());
    unordered_map<ll, My> used;
    bool fl = true;
    ll d = 0;
    ll g = 0;
    for (ll i = 0; i < n; i++) {
        for (ll j = i + 1; j < n; j++) {
            if (!used[a[j] - a[i]].start) {
                used[a[j] - a[i]].start = a[i];
                used[a[j] - a[i]].ind = i;
            }
            if (k - used[a[j] - a[i]].cnt > n - j) {
                used.erase(a[j] - a[i]);
            }
            used[a[j] - a[i]].cnt++;
            if (used[a[j] - a[i]].cnt == k-1) {
                d = a[j] - a[i];
                ll cnt = 0;
                cout << used[a[j] - a[i]].start << '\n';
                ll last = used[a[j] - a[i]].ind;
                for (ll f = used[a[j] - a[i]].ind+1; f < n&& cnt != k - 1; f++) {
                    if (a[f] - a[last] == d) {
                        cout <<a[f]<<'\n';
                        last = f;
                        cnt++;
                    }
                }
                return 0;
            }
        }
    }
}