Submission #300208

#	Time	Username	Problem	Language	Result	Execution time	Memory
300208		Yousef_Salama	Carnival Tickets (IOI20_tickets)	C++17	100 / 100	1522 ms	109716 KiB

tickets

#include "tickets.h"
#include <bits/stdc++.h>
using namespace std;
/*
void allocate_tickets(vector < vector <int> > s){
	int n = (int)s.size(), m = (int)s[0].size();
	
	for(int i = 0; i < n; i++){
		for(int j = 0; j < m; j++){
			if(j > 0)printf(" ");
			printf("%d", s[i][j]);
		}
		printf("\n");
	}
}
*/
long long find_maximum(int k, vector < vector <int> > x){
	int n = (int)x.size(), m = (int)x[0].size();
	
	long long total = 0;
	vector < pair <int, int> > r;
	vector <int> t(n, 0);
	
	for(int i = 0; i < n; i++){
		for(int j = k - 1; j >= 0; j--){
			r.emplace_back(x[i][j] + x[i][m - (k - 1 - j) - 1], i);
			total -= x[i][j];
		}
	}
	sort(r.rbegin(), r.rend());
	
	for(int i = 0; i < k * (n / 2); i++){
		total += r[i].first;
		t[r[i].second]++;
	}
	
	vector < pair <int, pair <int, int> > > v;
	for(int i = 0; i < n; i++){
		for(int j = 0; j < k - t[i]; j++)
			v.push_back({x[i][j], {i, j}});
		for(int j = 0; j < t[i]; j++)
			v.push_back({x[i][m - j - 1], {i, m - j - 1}});
	}
	sort(v.begin(), v.end());
	sort(v.begin(), v.begin() + k * (n / 2), [&](auto p, auto q){
			return p.second.first < q.second.first;
		});
	
	vector < vector <int> > w(n);
	vector <int> p(n, 0);
	
	for(int i = k * (n / 2); i < k * n; i++)
		w[v[i].second.first].push_back(v[i].second.second);
		
	vector < vector <int> > s(n, vector<int>(m, -1));
	
	for(int i = 0; i < k; i++){
		vector <bool> marked(n, false);
		for(int j = 0; j < n / 2; j++){
			s[v[i + j * k].second.first][v[i + j * k].second.second] = i;
			marked[v[i + j * k].second.first] = true;
		}
		for(int j = 0; j < n; j++)if(!marked[j]){
			s[j][w[j][p[j]++]] = i;
		}
	}
	allocate_tickets(s);
	
	return total;
}
/*
int main(){
	int n, m, k;
	scanf("%d %d %d", &n, &m, &k);
	
	vector < vector <int> > x(n, vector <int>(m));
	for(int i = 0; i < n; i++)
	for(int j = 0; j < m; j++)
		scanf("%d", &x[i][j]);
		
	printf("%lld\n", find_maximum(k, x));

	return 0;
}
*/

• 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