Submission #1153416

#	Time	Username	Problem	Language	Result	Execution time	Memory
1153416		Sharky	Carnival Tickets (IOI20_tickets)	C++20	100 / 100	783 ms	104196 KiB

tickets

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

using ll = long long;

ll find_maximum(int k, std::vector<std::vector<int>> x) {
	int n = x.size();
	int m = x[0].size();
	vector<vector<bool>> use(n, vector<bool> (m, 0));
	vector<vector<int>> answer(n, vector<int> (m, -1));
	ll ans = 0;
	vector<stack<int>> st(n);
	vector<vector<pair<int, int>>> a(n);
	priority_queue<pair<int, pair<int, int>>> q;
	for (int i = 0; i < n; i++) {
		vector<pair<int, int>> srt;
		for (int j = 0; j < m; j++) srt.push_back({x[i][j], j});
		sort(srt.begin(), srt.end());
		for (int j = 0; j < k; j++) {
			st[i].push(srt[j].second);
			ans -= srt[j].first;
			use[i][srt[j].second] = 1;
		}
		a[i] = srt;
	}
	for (int i = 0; i < n; i++) {
		q.push({a[i].back().first + x[i][st[i].top()], {i, st[i].top()}});
	}
	int cnt = 0;
	while (!q.empty()) {
		auto [v, pr] = q.top();
		auto [id, rw] = pr;
		q.pop();
		cnt++;
		use[id][rw] = 0;
		use[id][a[id].back().second] = 1;
		ans += v;
		a[id].pop_back();
		st[id].pop();
		if (!st[id].empty()) q.push({a[id].back().first + x[id][st[id].top()], {id, st[id].top()}});
		if (cnt >= (n*k)/2) break;
	}
	vector<array<int, 3>> val;
	for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) if (use[i][j]) val.push_back({x[i][j], i, j});
	sort(val.begin(), val.end(), [] (auto i, auto j) { return i[0] > j[0]; });
	vector<queue<int>> stk(n), stk2(n);
	for (int i = 0; i < val.size() / 2; i++) stk[val[i][1]].push(val[i][2]);
	for (int i = val.size() / 2; i < val.size(); i++) stk2[val[i][1]].push(val[i][2]);
	for (int rd = 0; rd < k; rd++) {
		vector<pair<int, int>> sz;
		for (int i = 0; i < n; i++) sz.push_back({stk[i].size(), i});
		sort(sz.rbegin(), sz.rend());
		for (int i = 0; i < n/2; i++) {
			int tp = stk[sz[i].second].front();
			stk[sz[i].second].pop();
			answer[sz[i].second][tp] = rd;
		}
		for (int i = n/2; i < n; i++) {
			int tp = stk2[sz[i].second].front();
			stk2[sz[i].second].pop();
			answer[sz[i].second][tp] = rd;
		}
	}
	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