Submission #540641

#	Time	Username	Problem	Language	Result	Execution time	Memory
540641		MilosMilutinovic	Carnival Tickets (IOI20_tickets)	C++14	27 / 100	473 ms	51404 KiB

tickets

#include "tickets.h"
#include <bits/stdc++.h>

using namespace std;

/*
at every round we choose n / 2 mins and n / 2 maxs
value of round is sum_of_maxs - sum_of_mins
mx[i] + mn[i] > mx[j] + mn[j]
    ^ wrong
   
just image taking k mins and then find diffs next max - last min
sort everything and take greedy
works?
*/

long long find_maximum(int k, vector<vector<int>> x) {
  int n = x.size(), m = x[0].size();
  vector<vector<int>> ans(n, vector<int>(m, -1));
  long long sum = 0;      
  vector<tuple<long long, int, int, int>> ops;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < k; j++) {
      sum -= x[i][j];
      ans[i][j] = j;
    }                       
    for (int j = k - 1; j >= 0; j--) {
      ops.emplace_back(x[i][j] + x[i][m - (k - j)], i, j, m - (k - j));
    }
  }
  int take = n / 2 * k;
  sort(ops.rbegin(), ops.rend());
  for (int id = 0; id < take; id++) {
    sum += get<0>(ops[id]);
    int i = get<1>(ops[id]);
    int jx = get<2>(ops[id]);
    int jy = get<3>(ops[id]);
    swap(ans[i][jx], ans[i][jy]);
  }
  allocate_tickets(ans);
  return sum;
}

• 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