Submission #629611

#	Time	Username	Problem	Language	Result	Execution time	Memory
629611		flashmt	Rarest Insects (IOI22_insects)	C++17	100 / 100	63 ms	444 KiB

insects

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

pair<vector<int>, vector<int>> findFirstOccurrences(vector<int> id, int maxC, int expectedSize)
{
  vector<int> good, bad;
  for (int i : id)
  {
    if (size(good) == expectedSize)
    {
      bad.push_back(i);
      continue;
    }

    move_inside(i);
    if (press_button() <= maxC) good.push_back(i);
    else
    {
      move_outside(i);
      bad.push_back(i);
    }
  }
  for (int i : good)
    move_outside(i);
  return {good, bad};
}

int min_cardinality(int n)
{
  vector<int> id(n);
  iota(begin(id), end(id), 0);
  auto [good, bad] = findFirstOccurrences(id, 1, n);
  int typeCnt = size(good);

  int ans = 1;
  id = bad;
  while (size(id) >= typeCnt)
  {
    int low = 1, high = size(id) / typeCnt, rem = size(id) % typeCnt;
    int mid = (low + high + (rem * 2 > typeCnt)) / 2;
    int expectedSize = typeCnt * mid;
    tie(good, bad) = findFirstOccurrences(id, mid, expectedSize);
    if (size(good) < expectedSize) id = good;
    else
    {
      ans += mid;
      id = bad;
    }
  }
  return ans;
}

Compilation message (stderr)

insects.cpp: In function 'std::pair<std::vector<int>, std::vector<int> > findFirstOccurrences(std::vector<int>, int, int)':
insects.cpp:10:20: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   10 |     if (size(good) == expectedSize)
      |         ~~~~~~~~~~~^~~~~~~~~~~~~~~
insects.cpp: In function 'int min_cardinality(int)':
insects.cpp:38:19: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   38 |   while (size(id) >= typeCnt)
      |          ~~~~~~~~~^~~~~~~~~~
insects.cpp:44:20: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   44 |     if (size(good) < expectedSize) id = good;
      |         ~~~~~~~~~~~^~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 75 / 75