Submission #303079

#	Time	Username	Problem	Language	Result	Execution time	Memory
303079		tutis	Carnival Tickets (IOI20_tickets)	C++17	100 / 100	1156 ms	62500 KiB

tickets

#include "tickets.h"
#include <vector>
#include <bits/stdc++.h>
using namespace std;
long long find_maximum(int k, vector<vector<int>> x) {
	int n = x.size();
	int m = x[0].size();
	bool vien = true;
	for (int i = 0; i < n; i++)
		for (int j = 0; j < m; j++)
			if (x[i][j] < 0 || x[i][j] > 1)
				vien = false;
	vector<vector<int>> answer(n, vector<int>(m, -1));
	int mxp = n / 2 * k;
	int P[n];
	vector<pair<int, int>>A;
	for (int i = 0; i < n; i++)
	{
		P[i] = 0;
		for (int j = 0; j < k; j++)
			A.push_back({x[i][k - 1 - j] + x[i][m - 1 - j], i});
	}
	sort(A.begin(), A.end(), greater<pair<int, int>>());
	for (int i = 0; i < (int)A.size() / 2; i++)
		P[A[i].second]++;
	int a[n];
	int b[n];
	for (int i = 0; i < n; i++)
	{
		a[i] = 0;
		b[i] = m - 1;
	}
	long long ret = 0;
	for (int g = 0; g < k; g++)
	{
		pair<int, int>xx[n];
		for (int i = 0; i < n; i++)
			xx[i] = {P[i], i};
		sort(xx, xx + n);
		for (int i = 0; i < n / 2; i++)
		{
			int id = xx[i].second;
			ret -= x[id][a[id]];
			answer[id][a[id]] = g;
			a[id]++;
		}
		for (int i = n / 2; i < n; i++)
		{
			int id = xx[i].second;
			ret += x[id][b[id]];
			answer[id][b[id]] = g;
			b[id]--;
			P[id]--;
		}
	}
	allocate_tickets(answer);
	return ret;
}

Compilation message (stderr)

tickets.cpp: In function 'long long int find_maximum(int, std::vector<std::vector<int> >)':
tickets.cpp:8:7: warning: variable 'vien' set but not used [-Wunused-but-set-variable]
    8 |  bool vien = true;
      |       ^~~~
tickets.cpp:14:6: warning: unused variable 'mxp' [-Wunused-variable]
   14 |  int mxp = n / 2 * k;
      |      ^~~

• 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