Submission #1084703

#	Time	Username	Problem	Language	Result	Execution time	Memory
1084703		siewjh	Rarest Insects (IOI22_insects)	C++17	100 / 100	46 ms	704 KiB

insects

#include "insects.h"
#include <bits/stdc++.h>
using namespace std;
int min_cardinality(int N){
	random_device rd;
	mt19937 g(rd());
	vector<int> active;
	int cnt = 0;
	for (int i = 0; i < N; i++){
		move_inside(i);
		if (press_button() == 1) cnt++;
		else{
			move_outside(i); active.push_back(i);
		}
	}
	shuffle(active.begin(), active.end(), g);
	int ans = 1, l = 2, r = N / cnt, sz = cnt;
	while (l <= r){
		int m = (l + r) >> 1;
		vector<int> iv, ov;
		for (int i : active){
			if (sz == cnt * m){
				ov.push_back(i); continue;
			}
			move_inside(i);
			if (press_button() <= m){
				iv.push_back(i); sz++;
			}
			else{
				move_outside(i); ov.push_back(i);
			}
		}
		if (sz == cnt * m){
			ans = m; l = m + 1;
			active = ov;
		}
		else{
			r = m - 1;
			for (int i : iv) move_outside(i);
			sz -= iv.size();
			active = iv;
		}
	}
	return ans;
}

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