Submission #318420

#	Time	Username	Problem	Language	Result	Execution time	Memory
318420		nickmet2004	Carnival Tickets (IOI20_tickets)	C++14	100 / 100	793 ms	76260 KiB

tickets

#include<bits/stdc++.h>
#include "tickets.h"
using namespace std;
int cnt[1505];
int n , m ,k;
vector<vector<int>>a;

long long find_maximum(int k , vector<vector<int>> a){
    int n = a.size() , m = a[0].size();
    /// nk/2 maximums - nk/2 minimums
    priority_queue<pair<int , int>> pq;
    long long ans = 0;
    for(int i = 0; i < n; ++i){
        for(int j = 0; j < k; ++j) ans += a[i][m - k + j];
        pq.emplace(-a[i][0] - a[i][m - k] , i);
    } /// --k
    for(int i = 0; i < n * k / 2; ++i){
        auto x = pq.top(); pq.pop();
        int q = x.second;
        ans += x.first;
        if(++cnt[q] < k) pq.emplace(-a[q][cnt[q]] - a[q][m - k + cnt[q]] , q);
    }
    vector<vector<int>> r(n , vector<int>(m , -1));
    /// nk/2 divide into n/2 groups
    int mnL = 0 , mxR = 0;
    for(int i = 0; i < n; ++i){
        for(int j = 0; j < cnt[i]; ++j) r[i][j] = mnL++ , mnL%= k;
        mxR = mnL;
        for(int j = m - k + cnt[i]; j < m; ++j) r[i][j] = mxR++ , mxR%= k;
    }
    allocate_tickets(r);
    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