Submission #776322

#	Time	Username	Problem	Language	Result	Execution time	Memory
776322		GusterGoose27	Rarest Insects (IOI22_insects)	C++17	100 / 100	58 ms	336 KiB

insects

#include "insects.h"

#include <bits/stdc++.h>

using namespace std;

const int MAXN = 1e5;

int min_cardinality(int n) {
    vector<int> perm(n);
    iota(perm.begin(), perm.end(), 0);
    mt19937 gen(chrono::steady_clock::now().time_since_epoch().count());
    for (int i = 1; i < n; i++) swap(perm[i], perm[gen()%(i+1)]);
	vector<int> reps;
	vector<int> extra;
	move_inside(perm[0]);
	int num_inside = 1;
	for (int i = 1; i < n; i++) {
		move_inside(perm[i]);
		if (press_button() > 1) {
			move_outside(perm[i]);
			extra.push_back(perm[i]);
		}
		else {
			num_inside++;
		}
	}
	int k = num_inside;
	if (k == 1) return n;
	while (extra.size() >= k) {
		int s = (extra.size()/2+k-1)/k;
		int base = num_inside/k;
		vector<int> l, r;
		for (int i = 0; i < s; i++) {
			move_inside(extra[i]);
			l.push_back(extra[i]);
		}
		for (int i = s; i < extra.size(); i++) {
			move_inside(extra[i]);
			if (press_button() > s+base) {
				move_outside(extra[i]);
				r.push_back(extra[i]);
			}
			else {
				l.push_back(extra[i]);
			}
		}
		if (l.size() == s*k) {
			extra = r;
			num_inside += l.size();
		}
		else {
			extra = l;
			for (int v: l) move_outside(v);
		}
	}
	return num_inside/k;
}

Compilation message (stderr)

insects.cpp: In function 'int min_cardinality(int)':
insects.cpp:30:22: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   30 |  while (extra.size() >= k) {
      |         ~~~~~~~~~~~~~^~~~
insects.cpp:38:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |   for (int i = s; i < extra.size(); i++) {
      |                   ~~^~~~~~~~~~~~~~
insects.cpp:48:16: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   48 |   if (l.size() == s*k) {
      |       ~~~~~~~~~^~~~~~

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