Submission #1300039

#	Time	Username	Problem	Language	Result	Execution time	Memory
1300039		trandangquang	Road Construction (JOI21_road_construction)	C++20	13 / 100	112 ms	18272 KiB

road_construction

/// gpt's code, not me
#include <bits/stdc++.h>
using namespace std;
using ll = long long;

struct Point {
    ll x, y;
    ll u, v;
    int id;
};

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int N;
    long long K;
    cin >> N >> K;

    vector<Point> p(N);
    for (int i = 0; i < N; i++) {
        cin >> p[i].x >> p[i].y;
        p[i].u = p[i].x + p[i].y;
        p[i].v = p[i].x - p[i].y;
        p[i].id = i;
    }

    sort(p.begin(), p.end(), [](auto &a, auto &b) {
        if (a.u != b.u) return a.u < b.u;
        return a.v < b.v;
    });

    // Min-heap of (distance, i, j)
    priority_queue<tuple<ll,int,int>, vector<tuple<ll,int,int>>, greater<>> pq;

    // Next pointer for each i
    vector<int> nxt(N);

    for (int i = 0; i < N; i++) {
        if (i + 1 < N) {
            ll dist = abs(p[i+1].x - p[i].x) + abs(p[i+1].y - p[i].y);
            pq.push({dist, i, i+1});
            nxt[i] = i + 1;
        } else {
            nxt[i] = -1;
        }
    }

    vector<ll> ans;
    ans.reserve(K);

    while (!pq.empty() && (long long)ans.size() < K) {
        auto [d, i, j] = pq.top();
        pq.pop();
        ans.push_back(d);

        // Move j forward for same i
        if (j + 1 < N) {
            ll nd = abs(p[j+1].x - p[i].x) + abs(p[j+1].y - p[i].y);
            pq.push({nd, i, j+1});
        }
    }

    for (auto x : ans) {
        cout << x << "\n";
    }

    return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 6 / 6
• Subtask 3: 7 / 7
• Subtask 4: 0 / 20
• Subtask 5: 0 / 27
• Subtask 6: 0 / 35