Submission #417561

#	Time	Username	Problem	Language	Result	Execution time	Memory
417561		ja_kingy	Carnival Tickets (IOI20_tickets)	C++14	100 / 100	950 ms	67808 KiB

tickets

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

typedef pair<int,int> pii;

long long find_maximum(int k, vector<vector<int>> x) {
	long long res = 0;
	int n = x.size();
	int m = x[0].size();
	vector<vector<int>> ans(n, vector<int>(m, -1));
	vector<pii> csts;
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < k; ++j) {
			res += x[i][m-1-j];
		}
		for (int j = 0; j < k; ++j) {
			csts.push_back({x[i][j]+x[i][m-k+j],i});
		}
	}
	vector<int> lcnt(n), hcnt(n, k);
	sort(csts.begin(), csts.end());
	for (int i = 0; i < n*k/2; ++i) {
		res -= csts[i].first;
		lcnt[csts[i].second]++;
		hcnt[csts[i].second]--;
	}
	for (int i = 0; i < k; ++i) {
		vector<int> vs(n);
		iota(vs.begin(), vs.end(), 0);
		sort(vs.begin(), vs.end(), [&](int a, int b) {return lcnt[a] > lcnt[b];});
		for (int j = 0; j < n/2; ++j) {
			lcnt[vs[j]]--;
			ans[vs[j]][lcnt[vs[j]]] = i;
		}
		for (int j = n/2; j < n; ++j) {
			hcnt[vs[j]]--;
			ans[vs[j]][m-1-hcnt[vs[j]]] = i;
		}
	}
	allocate_tickets(ans);
	return res;
}

• 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