Submission #652081

#	Time	Username	Problem	Language	Result	Execution time	Memory
652081		mychecksedad	Carnival Tickets (IOI20_tickets)	C++17	27 / 100	526 ms	70612 KiB

tickets

#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
#define pb push_back
#define all(x) x.begin(), x.end()

void allocate_tickets(vector<vector<int>> _x);

long long find_maximum(int k, vector<vector<int>> _arr) {
	vector<deque<ll>> arr (_arr.size());
	for(int i = 0; i < _arr.size(); ++i){
		for(int x: _arr[i]) arr[i].pb(x);
	}
	int n = arr.size();
	int m = arr[0].size();
	vector<vector<int>> answer;
	
	for (int i = 0; i < n; i++) {
		std::vector<int> row(m, -1);
		answer.push_back(row);
	}

	ll ans = 0;
	vector<int> poppedfront(n), poppedback(n);
	int M = m;
	for(int _ = 0; _ < k; ++_){
		vector<pair<ll, int>> a;
		for(int i = 0; i < n; ++i) a.pb({arr[i][0] + arr[i][m - 1], i});

		sort(all(a));

		for(int i = 0; i < n/2; ++i){
			int x = a[n - i - 1].second, y = a[i].second;
			ans += arr[x][m - 1] - arr[y][0];
			answer[x][m - 1 - poppedback[x]] = _;
			answer[y][poppedfront[y]] = _;
			arr[x].pop_back();
			arr[y].pop_front();
			poppedfront[y]++;
			poppedback[x]++;
		}
		m--;
	}

	allocate_tickets(answer);
	return ans;
}

Compilation message (stderr)

tickets.cpp: In function 'long long int find_maximum(int, std::vector<std::vector<int> >)':
tickets.cpp:11:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |  for(int i = 0; i < _arr.size(); ++i){
      |                 ~~^~~~~~~~~~~~~
tickets.cpp:25:6: warning: unused variable 'M' [-Wunused-variable]
   25 |  int M = m;
      |      ^

• Subtask 1: 11 / 11
• Subtask 2: 16 / 16
• Subtask 3: 0 / 14
• Subtask 4: 0 / 14
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23
• Subtask 7: 0 / 10