Submission #428648

#	Time	Username	Problem	Language	Result	Execution time	Memory
428648		alireza_kaviani	Carnival Tickets (IOI20_tickets)	C++17	100 / 100	1115 ms	73444 KiB

tickets

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

typedef long long ll;
typedef pair<int, int> pii;

#define sep		' '

const int MAXN = 1510;
int ptr[MAXN] , sum[MAXN] , L[MAXN] , R[MAXN] , F[MAXN][MAXN];

long long find_maximum(int k, vector<vector<int>> x) {
	int n = x.size() , m = x[0].size();
	ll ans = 0 , S = 0;
	vector<pii> vec;
	vector<vector<int>> answer;
	for (int i = 0; i < n; i++) {
		vector<int> row(m , 0);
		for (int j = 0; j < k; j++) {
			ans += x[i][m - k + j]; F[i][m - k + j] = 1;
			vec.push_back({x[i][j] + x[i][m - k + j] , i});
		}
		answer.push_back(row);
	}
	sort(vec.begin(), vec.end());
	for(int i = 0 ; i < n * k / 2 ; i++){
		int val = vec[i].first , id = vec[i].second;
		ans -= val; //cout << val << sep << id << endl;
		F[id][m - k + ptr[id]] = 0; F[id][ptr[id]] = -1; 
		ptr[id]++;
	}
	for(int i = 0 ; i < n ; i++){
		L[i] = 0; R[i] = m - 1;
		for(int j = 0 ; j < m ; j++){
			sum[i] += F[i][j];
			answer[i][j] = -1;
			S += F[i][j] * x[i][j];
	//		cout << F[i][j] << sep;
		}
	//	cout << endl;
	}
	//cout << S << sep << ans << endl;
	//assert(S == ans);
	for(int i = 0 ; i < k ; i++){
		vector<pii> v;
		for(int j = 0 ; j < n ; j++){
			v.push_back({sum[j] , j});
		}
		sort(v.begin(), v.end());
		for(int j = 0 ; j < n ; j++){
			int id = v[j].second;
			if(j < n / 2){
				sum[id]++;
				answer[id][L[id]++] = i;
			}
			else{
				sum[id]--;
				answer[id][R[id]--] = i;
			}
		}
	}
	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