Submission #632560

#	Time	Username	Problem	Language	Result	Execution time	Memory
632560		_Avocado_	Rarest Insects (IOI22_insects)	C++17	96.45 / 100	56 ms	428 KiB

insects

#include "insects.h"
#include <bits/stdc++.h>
using namespace std;
 
int min_cardinality(int n){
	vector<int>unique(n);
	int unique_cnt = 0;
	for(int i = 0; i<n; ++i){
		move_inside(i);
		int q = press_button();
		if(q == 1){
			unique[i] = 1;
			++unique_cnt;
		}
		else move_outside(i);
	}
	
	int r = n/unique_cnt;
	int l = 2;
	int ans = 1;
	
	vector<int>cur;
	
	for(int i = 0; i<n; ++i){
		if(!unique[i]) cur.push_back(i);
	}
	
	random_shuffle(cur.begin(), cur.end());
	
	while(l <= r){
		int m = (r+l)/2;
		vector<int>high, low;
		for(int i = 0; i<cur.size(); ++i){
			if(low.size() == (m-ans)*unique_cnt){
				high.push_back(cur[i]);
				continue;
			}
			move_inside(cur[i]);
			int q = press_button();
			if(q > m){
				high.push_back(cur[i]);
				move_outside(cur[i]);
			}
			else{
				low.push_back(cur[i]);
			}
		}
	
		if(low.size() != (m-ans)*unique_cnt){
			for(int i = 0; i<cur.size(); ++i){
				move_outside(cur[i]);
			}
			cur = low;
			r = m-1;
		}
		else{
			cur = high;
			l = m+1;
			ans = m;
		}
	}
			
	return ans;	
 
}

Compilation message (stderr)

insects.cpp: In function 'int min_cardinality(int)':
insects.cpp:33:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |   for(int i = 0; i<cur.size(); ++i){
      |                  ~^~~~~~~~~~~
insects.cpp:34:18: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   34 |    if(low.size() == (m-ans)*unique_cnt){
      |       ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
insects.cpp:49:17: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   49 |   if(low.size() != (m-ans)*unique_cnt){
      |      ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
insects.cpp:50:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |    for(int i = 0; i<cur.size(); ++i){
      |                   ~^~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 71.45 / 75