Submission #1270249

#	Time	Username	Problem	Language	Result	Execution time	Memory
1270249		tvdan	Drvca (COCI19_drvca)	C++20	0 / 110	18 ms	3148 KiB

drvca

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

bool check_ap(const vector<ll>& v) {
    if (v.size() <= 1) return true;
    ll d = v[1] - v[0];
    for (size_t i = 2; i < v.size(); ++i)
        if (v[i] - v[i-1] != d) return false;
    return true;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n;
    if (!(cin >> n)) return 0;
    vector<ll> a(n);
    for (int i = 0; i < n; ++i) cin >> a[i];
    sort(a.begin(), a.end());
    if (n == 2) {
        cout << 1 << "\n" << a[0] << "\n" << 1 << "\n" << a[1] << "\n";
        return 0;
    }
    vector<pair<int,int>> seeds;
    seeds.emplace_back(0,1);
    seeds.emplace_back(0,2);
    seeds.emplace_back(1,2);

    for (auto [p,q] : seeds) {
        if (p < 0 || q < 0 || p >= n || q >= n) continue;
        if (p == q) continue;
        vector<bool> used(n,false);
        vector<ll> r1, r2;
        if (p > q) swap(p,q);
        r1.push_back(a[p]);
        r1.push_back(a[q]);
        used[p] = used[q] = true;
        ll d1 = a[q] - a[p];
        ll last1 = a[q];

        for (int i = 0; i < n; ++i) {
            if (used[i]) continue;
            ll x = a[i];
            if (x == last1 + d1) {
                r1.push_back(x);
                last1 = x;
                used[i] = true;
            } else {
                r2.push_back(x);
                used[i] = true;
            }
        }
        if (r2.empty()) {
            continue;
        }
        if (check_ap(r2)) {
            cout << (int)r1.size() << "\n";
            for (size_t i = 0; i < r1.size(); ++i) {
                if (i) cout << ' ';
                cout << r1[i];
            }
            cout << "\n" << (int)r2.size() << "\n";
            for (size_t i = 0; i < r2.size(); ++i) {
                if (i) cout << ' ';
                cout << r2[i];
            }
            cout << "\n";
            return 0;
        }
    }

    cout << -1 << "\n";
    return 0;
}

• Subtask 1: 0 / 20
• Subtask 2: 0 / 30
• Subtask 3: 0 / 30
• Subtask 4: 0 / 30