Submission #1220045

#	Time	Username	Problem	Language	Result	Execution time	Memory
1220045		omsincoconut	Carnival Tickets (IOI20_tickets)	C++17	27 / 100	3095 ms	51484 KiB

tickets

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;

const ll INF = 1e18;

void allocate_tickets(vector<vector<int>> _x);

ll find_maximum(int k, vector<vector<int>> d) {
    int n = d.size(), m = d[0].size();
    
    priority_queue<pair<int, int>> pq;
    for (int i = 0; i < n; i++) {
        pq.emplace(d[i][m-1] + d[i][k-1], i);
    }

    vector<int> taken(n, 0);
    int cnt = n*k/2;
    while (cnt) {
        int id = pq.top().second;
        pq.pop();
        taken[id]++;
        cnt--;

        if (taken[id] < k) pq.emplace(d[id][m-1-taken[id]] + d[id][k-1-taken[id]], id);
    }

    vector<vector<int>> alloc(n, vector<int>(m, -1));
    vector<vector<bool>> have(k, vector<bool>(n, false));
    vector<int> ccnt(k, 0);
    vector<int> ptr(n, 0);

    vector<tuple<int, int, int>> more_tickets, less_tickets;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < taken[i]; j++) {
            more_tickets.emplace_back(d[i][m-j-1], i, m-j-1);
        }
        for (int j = 0; j < k-taken[i]; j++) {
            less_tickets.emplace_back(d[i][j], i, j);
        }
    }

    sort(more_tickets.begin(), more_tickets.end());
    sort(less_tickets.begin(), less_tickets.end());
    reverse(more_tickets.begin(), more_tickets.end());
    reverse(less_tickets.begin(), less_tickets.end());

    for (auto [val, i, j] : more_tickets) {
        while (have[ptr[i]][i] || ccnt[ptr[i]] >= n/2) ptr[i] = (ptr[i]+1)%k;
        have[ptr[i]][i] = true;
        ccnt[ptr[i]]++;
        alloc[i][j] = ptr[i];
    }

    ptr = vector<int>(n, 0);

    for (auto [val, i, j] : less_tickets) {
        while (have[ptr[i]][i] || ccnt[ptr[i]] >= n) ptr[i] = (ptr[i]+1)%k;
        have[ptr[i]][i] = true;
        ccnt[ptr[i]]++;
        alloc[i][j] = ptr[i];
    }

    allocate_tickets(alloc);

    ll ans = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < taken[i]; j++) {
            ans += d[i][m-j-1];
        }
        for (int j = 0; j < k-taken[i]; j++) {
            ans -= d[i][j];
        }
    }

    return ans;
}

• Subtask 1: 11 / 11
• Subtask 2: 16 / 16
• Subtask 3: 0 / 14
• Subtask 4: 0 / 14
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23
• Subtask 7: 0 / 10