Submission #423045

#	Time	Username	Problem	Language	Result	Execution time	Memory
423045		peijar	카니발 티켓 (IOI20_tickets)	C++17	11 / 100	2 ms	588 KiB

tickets

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

long long find_maximum(int k, vector<vector<int>> x) {
  int n = x.size();
  int m = x[0].size();
  vector<vector<int>> answer(n, vector<int>(m, -1));

  if (m == 1) {
    assert(k == 1);
    vector<int> elements;
    for (int i(0); i < n; ++i) {
      answer[i][0] = 0;
      elements.push_back(x[i][0]);
    }
    allocate_tickets(answer);

    long long ans = 0;
    sort(elements.begin(), elements.end());
    int mid = elements[n / 2];
    for (int v : elements)
      ans += abs(mid - v);
    return ans;
  } else if (k == 1) {
    vector<pair<int, int>> pairs(n);
    vector<bool> pickSide;
    long long sol = -1;
    for (int i(0); i < n; ++i)
      pairs[i] = make_pair(x[i][0], x[i].back());

    auto calcAns = [&](int mediane) {
      priority_queue<pair<int, int>> bstRemoved;
      vector<bool> side(n);
      long long curSol = 0;
      int neededRight = n / 2;
      for (int i(0); i < n; ++i) {
        if (pairs[i].second < mediane) {
          curSol += mediane - pairs[i].first;
          continue;
        }

        curSol += pairs[i].second - mediane;
        side[i] = 1;
        if (pairs[i].first > mediane)
          neededRight--;
        else
          bstRemoved.emplace(2 * mediane - (pairs[i].first + pairs[i].second),
                             i);
        while ((int)bstRemoved.size() > neededRight) {
          auto [delta, pos] = bstRemoved.top();
          bstRemoved.pop();
          curSol += delta;
          side[pos] = 0;
        }
      }
      int cnt = 0;
      for (auto v : side)
        cnt += v;
      if (cnt == n / 2 and curSol > sol)
        sol = curSol, pickSide = move(side);
    };

    for (auto [med1, med2] : pairs)
      calcAns(med1), calcAns(med2);
    for (int i(0); i < n; ++i) {
      if (pickSide[i])
        answer[i].back() = 0;
      else
        answer[i][0] = 0;
    }
    allocate_tickets(answer);
    return sol;
  }

  allocate_tickets(answer);
  return 1;
}

• 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