Submission #300849

#	Time	Username	Problem	Language	Result	Execution time	Memory
300849		Temmie	Carnival Tickets (IOI20_tickets)	C++17	100 / 100	1391 ms	78644 KiB

tickets

#include <bits/stdc++.h>

typedef long long ll;
typedef unsigned long long ull;

void allocate_tickets(std::vector <std::vector <int>> s);

int n, m;

ull find_maximum(int k, std::vector <std::vector <int>> x) {
	
	n = x.size();
	m = x[0].size();
	ll r = 0;
	for (int i = 0; i < n; i++)
		for (int j = m - 1; j > m - 1 - k; j--)
			r += x[i][j];
	std::vector <std::pair <int, int>> range(n, { -1, m - k });
	std::priority_queue <std::pair <int, int>> pq;
	for (int i = 0; i < n; i++)
		pq.push({ - x[i][range[i].first + 1] - x[i][range[i].second], i });
	for (int i = 0; i < (n * k) >> 1; i++) {
		auto p = pq.top(); pq.pop();
		r += p.first;
		range[p.second].first++, range[p.second].second++;
		if (range[p.second].second == m) continue;
		pq.push({ - x[p.second][range[p.second].first + 1] - x[p.second][range[p.second].second], p.second });
	}
	std::vector <std::vector <int>> mx(n), mn(n), mxi(n), mni(n);
	for (int i = 0; i < n; i++) {
		for (int j = 0; j <= range[i].first; j++)
			mn[i].push_back(x[i][j]), mni[i].push_back(j);
		for (int j = range[i].second; j < m; j++)
			mx[i].push_back(x[i][j]), mxi[i].push_back(j);;
		std::reverse(mn[i].begin(), mn[i].end());
		std::reverse(mni[i].begin(), mni[i].end());
	}
	std::vector <std::vector <int>> ans(n, std::vector <int> (m, -1));
	for (int i = 0; i < k; i++) {
		int hasmn = 0;
		std::vector <int> mnmx(n, 0);
		std::priority_queue <std::pair <int, int>> pqq;
		for (int j = 0; j < n; j++) {
			if (mx[j].size()) {
				mnmx[j] = 1;
				if (mn[j].size()) {
					pqq.push({ - mn[j].back() - mx[j].back(), j });
				}
			} else {
				mnmx[j] = -1;
				hasmn++;
			}
		}
		while (hasmn < (n >> 1)) {
			auto p = pqq.top(); pqq.pop();
			mnmx[p.second] = -1;
			hasmn++;
		}
		for (int j = 0; j < n; j++) {
			if (mnmx[j] == 1) {
				ans[j][mxi[j].back()] = i;
				mx[j].pop_back();
				mxi[j].pop_back();
			} else {
				ans[j][mni[j].back()] = i;
				mn[j].pop_back();
				mni[j].pop_back();
			}
		}
	}
	allocate_tickets(ans);
	return r;
	
}

• 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