Submission #1316496

#	Time	Username	Problem	Language	Result	Execution time	Memory
1316496		nikaa123	카니발 티켓 (IOI20_tickets)	C++20	100 / 100	430 ms	75304 KiB

tickets

#include <bits/stdc++.h>
#include "tickets.h"
using namespace std;

long long find_maximum(int k, vector<std::vector<int>> x) {
	int n = x.size();
	int m = x[0].size();
	vector<std::vector<int>> answer;
	vector <vector<int>> st(n,vector<int>(m,0));
	long long ans = 0;
	for (int i = 0; i < n; i++) {
		std::vector<int> row(m);
		for (int j = 0; j < m; j++) {
			if (j < k) {
				row[j] = -1;
			} else {
				row[j] = -1;
			}
		}
		answer.push_back(row);
	}
	int l[n]; int r[n];
	priority_queue<pair<long long,int>> q;
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < k; j++) {
			st[i][j] = -1;
		}
		l[i] = k-1; r[i] = m-1; 
		q.push({x[i][r[i]]+x[i][l[i]],i});
	}
	for (int t = 0; t < k*n/2; t++) {
		auto [gain,i] = q.top();
		q.pop();
		st[i][l[i]] = 0;
		st[i][r[i]] = 1;
		l[i]--;
		r[i]--;
		long long ngain = -LLONG_MAX;
		if (l[i] >= 0) ngain = x[i][r[i]]+x[i][l[i]];
		q.push({ngain,i});
	}
	vector <vector<int>> mn(n),pl(n);
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < m; j++) {
			ans += st[i][j] * x[i][j];
			if (st[i][j] == 1) {
				pl[i].push_back(j);
			}
			if (st[i][j] == -1) {
				mn[i].push_back(j);
			}
		}
	}
	for (int i = 0; i < k; i++) {
		vector <int> idx(n);
		iota(idx.begin(),idx.end(),0);
		sort(idx.begin(),idx.end(),[&](int a, int b){
			return pl[a].size() > pl[b].size();
		});
		for (int j = 0; j < n; j++) {
			int cur = idx[j];
			if (j < n/2) {
				answer[cur][pl[cur].back()] = i;
				pl[cur].pop_back();
			} else {
				answer[cur][mn[cur].back()] = i;
				mn[cur].pop_back();
			}
		}
	}

	allocate_tickets(answer);
	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