Submission #370947

#	Time	Username	Problem	Language	Result	Execution time	Memory
370947		pit4h	Carnival Tickets (IOI20_tickets)	C++14	100 / 100	1091 ms	93088 KiB

tickets

#include "tickets.h"
#include<bits/stdc++.h>
#define st first
#define nd second
#define mp make_pair
using namespace std;
using ll = long long;
using pii = pair<int, int>;

ll find_maximum(int k, vector<vector<int>> x) {
	int n = x.size();
	int m = x[0].size();
	vector<vector<int>> answer(n, vector<int>(m, -1));

	ll ans = 0;

	vector<vector<int>> vec(n, vector<int>(m));
	vector<pii> all;

	for(int i=0; i<n; ++i) {
		for(int j=m-k; j<m; ++j) {
			ans += x[i][j];
			vec[i][j-(m-k)] = x[i][j] + x[i][j-(m-k)];
			all.push_back(mp(vec[i][j-(m-k)], i));
		}
	}

	sort(all.begin(), all.end());

	vector<int> cnt(n), l(n), r(n, m-1);

	for(int i=0; i<k*n/2; ++i) {
		cnt[all[i].nd]++;	
		ans -= all[i].st;
	}

	for(int i=0; i<k; ++i) {
		vector<pii> v;
		for(int j=0; j<n; ++j) {
			v.push_back(mp(cnt[j], j));
		}
		sort(v.begin(), v.end());
		for(int j=0; j<n/2; ++j) {
			int it = v[j].nd;			
			answer[it][r[it]] = i;
			r[it]--;
		}
		for(int j=n/2; j<n; ++j) {
			int it = v[j].nd;
			answer[it][l[it]] = i;
			l[it]++;
			cnt[it]--;
		}
	}

	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