Submission #630992

#	Time	Username	Problem	Language	Result	Execution time	Memory
630992		blue	Rarest Insects (IOI22_insects)	C++17	47.50 / 100	243 ms	560 KiB

insects

#include "insects.h"
#include <vector>
#include <iostream>
using namespace std;

using vi = vector<int>;
using vvi = vector<vi>;

const int mx = 2'000;

vi ins(mx, 0);
int ct = 0;

void move_in(int i)
{
	// cerr << "insert " << i << '\n';
	if(ins[i]) 
		return;

	ins[i] = 1;
	move_inside(i);
	ct++;
}

void move_out(int i)
{
	// cerr << "erase " << i << '\n';
	if(!ins[i])
		return;

	ins[i] = 0;
	move_outside(i);
	ct--;
}

int min_cardinality(int N)
{
	int tot = 0;

	vi is_basic(N, 0);

	for(int i = 0; i < N; i++)
	{
		move_in(i);
		if(press_button() >= 2)
			move_out(i);
		else
		{
			is_basic[i] = 1;
			tot++;
		}
	}

	for(int i = 0; i < N; i++)
		move_out(i);

	// cerr << "tot = " << tot << '\n';

	vi currlist;
	for(int i = 0; i < N; i++)
		currlist.push_back(i);

	int lo = 0, hi = N;
	while(lo != hi)
	{
		int mid = (lo+hi)/2 + 1;
		// cerr << lo << ' ' << hi << " : " << mid << '\n';

		vi inlist, outlist;

		for(int i : currlist)
		{
			if(ins[i])
				continue;
			move_in(i);
			if(press_button() > mid)
			{
				outlist.push_back(i);
				move_out(i);
			}
			else
				inlist.push_back(i);
		}	

		// cerr << "ct = " << ct << '\n';

		if(ct == mid * tot)
		{
			lo = mid;
		}
		else
		{
			hi = mid - 1;
			for(int f : inlist)
				move_out(f);
		}
	}
	
	return lo;
}

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 22.5 / 75