Submission #726658

#	Time	Username	Problem	Language	Result	Execution time	Memory
726658		Mamedov	Rarest Insects (IOI22_insects)	C++17	100 / 100	59 ms	412 KiB

insects

#include "insects.h"
#pragma GCC optimize ("O3")
#include <bits/stdc++.h>
#define pii pair<int, int>
#define piii pair<pii, int>
#define vi vector<int>
#define vll vector<ll>
#define vvi vector<vi>
#define vpii vector<pii>
#define vvpii vector<vpii>
#define f first
#define s second
#define oo 1000000001
#define eb emplace_back
#define pb push_back
#define mpr make_pair
#define size(v) (int)v.size()
#define ln '\n'
#define ull unsigned long long
#define ll long long
#define all(v) v.begin(), v.end()

using namespace std;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int min_cardinality(int N) {
  vector<bool>inside(N, false);
  vector<bool>fixed(N, false);
  vi machine;

  for (int i = 0; i < N; ++i) {
    move_inside(i);
    if (press_button() == 2) {
      move_outside(i);
    } else {
      inside[i] = fixed[i] = true;
      machine.eb(i);
    }
  }

  int uni = size(machine);
  int l = 1, r = N / uni;

  vi p(N);
  for (int i = 0; i < N; ++i) {
    p[i] = i;
  }
  shuffle(all(p), rng);

  while (l < r) {
    int mid = (l + r + 1) >> 1;
    for (int i : p) {
      if (uni * mid == size(machine)) break;
      if (!fixed[i]) {
        move_inside(i);
        if (press_button() > mid) {
          move_outside(i);
        } else {
          inside[i] = true;
          machine.eb(i);
        }
      }
    }
    if (uni * mid == size(machine)) {
      l = mid;
      for (int i = 0; i < N; ++i) {
        if (inside[i]) fixed[i] = true;
      }
    } else {
      r = mid - 1;
      for (int i = 0; i < N; ++i) {
        if (!inside[i]) {
          fixed[i] = true;
        } else if (!fixed[i]) {
          move_outside(i);
          inside[i] = false;
          machine.pop_back();
        }
      }
    }
  }
  return l;
}

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