Submission #518382

#	Time	Username	Problem	Language	Result	Execution time	Memory
518382		Plurm	Carnival Tickets (IOI20_tickets)	C++17	11 / 100	150 ms	680 KiB

tickets

#include "tickets.h"
#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();
	vector<vector<int>> answer;
	for (int i = 0; i < n; i++) {
		vector<int> row(m);
		for (int j = 0; j < m; j++) {
			row[j] = -1;
		}
		answer.push_back(row);
	}
  long long ans = 0ll;
  for(int t = 0; t < k; t++){
    set<int> used_rows;
    for(int tt = 0; tt < n/2; tt++){
      // try 1
      int mx1 = -1;
      int mx1row = -1;
      int mx1col = -1;
      for(int i = 0; i < n; i++){
        if(used_rows.count(i)) continue;
        for(int j = 0; j < m; j++){
          if(answer[i][j] == -1){
            if(x[i][j] > mx1){
              mx1 = x[i][j];
              mx1row = i;
              mx1col = j;
            }
          }
        }
      }
      int mn1 = 1e9+1;
      int mn1row = -1;
      int mn1col = -1;
      for(int i = 0; i < n; i++){
        if(used_rows.count(i) || i == mx1row) continue;
        for(int j = 0; j < m; j++){
          if(answer[i][j] == -1){
            if(x[i][j] < mn1){
              mn1 = x[i][j];
              mn1row = i;
              mn1col = j;
            }
          }
        }
      }
      // try 2
      int mn2 = 1e9+1;
      int mn2row = -1;
      int mn2col = -1;
      for(int i = 0; i < n; i++){
        if(used_rows.count(i)) continue;
        for(int j = 0; j < m; j++){
          if(answer[i][j] == -1){
            if(x[i][j] < mn2){
              mn2 = x[i][j];
              mn2row = i;
              mn2col = j;
            }
          }
        }
      }
      int mx2 = -1;
      int mx2row = -1;
      int mx2col = -1;
      for(int i = 0; i < n; i++){
        if(used_rows.count(i) || i == mn2row) continue;
        for(int j = 0; j < m; j++){
          if(answer[i][j] == -1){
            if(x[i][j] > mx2){
              mx2 = x[i][j];
              mx2row = i;
              mx2col = j;
            }
          }
        }
      }
      if(mx2 - mn2 > mx1 - mn1){
        answer[mx2row][mx2col] = t;
        answer[mn2row][mn2col] = t;
        ans += mx2 - mn2;
        used_rows.insert(mx2row);
        used_rows.insert(mn2row);
      }else{
        answer[mx1row][mx1col] = t;
        answer[mn1row][mn1col] = t;
        ans += mx1 - mn1;
        used_rows.insert(mx1row);
        used_rows.insert(mn1row);
      }
    }
  }
	allocate_tickets(answer);
	return ans;
}

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