오류로 글이 2개 떠있었는데 오류인지 모르고 하나 삭제했더니 둘 다 삭제돼서 다시 쓰는 벨로그

문제

입력

입출력 예시

코드

#include <iostream>
#include <vector>
#include <queue>
#include <set>
#include <algorithm>
using namespace std;

int N, M;
vector<vector<int>> computer;
vector<int> visit;

pair<float, vector<int>> bfs(int start) {
	vector<int> component;
	set<pair<int, int>> circuit;
	float cnt = 1;
	visit[start] = 1;
	queue<int> q;
	q.push(start);
	component.emplace_back(start);
	
	while(!q.empty()) {
		int now = q.front();
		q.pop();
		if(computer[now].empty()) continue;
		for(int i : computer[now]) {
			if(now < i) circuit.insert({now, i});
			else circuit.insert({i, now});
			if(!visit[i]) {
				visit[i] = 1;
				q.push(i);
				component.emplace_back(i);
				++cnt;
			}
		}
	}
	return {float(circuit.size()) / cnt, component};
}

vector<int> bfsAll() {
	float max = 0.0;
	vector<int> component;
	for(int i = 1; i <= N; i++) {
		if(!visit[i]) {
			pair<float, vector<int>> now = bfs(i);
			float density = now.first;
			if(density > max) {
				max = density;
				component = now.second;
			}
			else if(density == max) {
				if(component.size() < now.second.size()){
					component = now.second;
				}
				else if(component.size() == now.second.size()) {
					if(component[0] > now.second[0])
						component = now.second;
				}
			}
		}
		
	}
	return component;
}

int main() {
	cin >> N >> M;
	computer = vector<vector<int>>(N + 1, vector<int>(0, 0));
	visit = vector<int>(N + 1, 0);
	
	for(int i = 0; i < M; i++) {
		int a, b;
		cin >> a >> b;
		computer[a].emplace_back(b);
		computer[b].emplace_back(a);
	}
	
	vector<int> v = bfsAll();
	sort(v.begin(), v.end());
	for(int i : v){
		cout << i << " ";
	}
	return 0;
}