Submission #658791

#	Time	Username	Problem	Language	Result	Execution time	Memory
658791		pere_gil	Rarest Insects (IOI22_insects)	C++17	0 / 100	34 ms	288 KiB

insects

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

bool in[2005],bad[2005];
int tot_in=0,dif;

bool check(int n, int x){
	vector<int> inside,out;
	for(int i=0;i<n;i++){
		if(in[i] || bad[i]) continue;

		move_inside(i);
		if(press_button()>x) out.push_back(i);
		else inside.push_back(i);

		if(tot_in+(int)inside.size()==x*dif) break;
	}

	if(tot_in+(int)inside.size()==x*dif){
		tot_in+=inside.size();
		for(int i: inside) in[i]=true;
		for(int i: out) move_outside(i);
		return true;
	}

	for(int i: inside) move_outside(i);
	for(int i: out){
		move_outside(i);
		bad[i]=true;
	}
	return false;
}

int min_cardinality(int n) {
	memset(in,false,sizeof in);
	memset(bad,false,sizeof bad);
	tot_in=0;

	for(int i=0;i<n;i++){
		move_inside(i);
		if(press_button()>1) move_outside(i);
		else{
			in[i]=true;
			tot_in++;
		}
	}
	dif=tot_in;

	if(dif==1) return n;
	
	int l=1,r=n/dif+1;
	while(l+1<r){
		int med=(l+r)/2;
		if(check(n,med)) l=med;
		else r=med;
	}
    	
	return l;
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 15
• Subtask 3: 0 / 75