제출 #704635

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
704635		bebra	카니발 티켓 (IOI20_tickets)	C++17	100 / 100	899 ms	77516 KiB

tickets

#include "tickets.h"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
 
#define dbg(x) cerr << #x << ": " << x << endl;
 
 
ll find_maximum(int k, vector<vector<int>> x) {
    int n = x.size();
    int m = x[0].size();

    vector<vector<int>> res(n, vector<int>(m, -1));
    vector<vector<int>> sign(n, vector<int>(m));
    vector<vector<int>> minus_sign(n);
    vector<vector<int>> plus_sign(n);

    priority_queue<pair<int, int>> pq;

    vector<int> first(n, k - 1);
    vector<int> last(n, m - 1);

    ll ans = 0;
    for (int i = 0; i < n; ++i) {
        pq.emplace(x[i][first[i]] + x[i][last[i]], i);
        for (int j = 0; j < k; ++j) {
            sign[i][j] = -1;
            ans -= x[i][j];
        }
    }

    for (int t = 0; t < n * k / 2; ++t) {
        auto [value, i] = pq.top();
        pq.pop();
        ans += value;

        sign[i][first[i]] = 0;
        sign[i][last[i]] = 1;

        if (first[i] > 0) {
            --first[i];
            --last[i];
            pq.emplace(x[i][first[i]] + x[i][last[i]], i);
        }
    }

    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            if (sign[i][j] == 1) plus_sign[i].push_back(j);
            else if (sign[i][j] == -1) minus_sign[i].push_back(j);
        }
    }

    for (int t = 0; t < k; ++t) {
        vector<int> p(n);
        iota(p.begin(), p.end(), 0);
        sort(p.begin(), p.end(), [&](int lhs, int rhs) {
            return plus_sign[lhs].size() < plus_sign[rhs].size();
        });

        for (int i = 0; i < n / 2; ++i) {
            res[p[i]][minus_sign[p[i]].back()] = t;
            minus_sign[p[i]].pop_back();
        }
        for (int i = n / 2; i < n; ++i) {
            res[p[i]][plus_sign[p[i]].back()] = t;
            plus_sign[p[i]].pop_back();
        }
    }
    
    allocate_tickets(res);
    return ans;
}

• Subtask 1: 11 / 11
• Subtask 2: 16 / 16
• Subtask 3: 14 / 14
• Subtask 4: 14 / 14
• Subtask 5: 12 / 12
• Subtask 6: 23 / 23
• Subtask 7: 10 / 10