백준 24479 c++

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

vector <int> graph[200001];//벡터 배열 : 정수배열 200001개가 아님
bool visited[200001];
int result[200001];
int cnt = 0;

void input_graph(int M)
{
	int i, u, v;

	for (i = 1; i <= M; i++)
	{
		cin >> u >> v;
		graph[u].push_back(v);
		graph[v].push_back(u);
	}
	for (i = 1; i <= M; i++)
	{
		sort(graph[i].begin(), graph[i].end());
	}

	return;
}

void dfs(int n)
{
	int i;

	if (visited[n] == true)
	{
		return;
	}
	else
	{
		visited[n] = true;
		cnt++;
		result[n] = cnt;
		for (i = 0; i < graph[n].size(); i++)
		{
			dfs(graph[n][i]);
		}
	}
}

int main(void)
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);

	int N, M, R;

	cin >> N >> M >> R;
	input_graph(M);
	dfs(R);
	for (int i = 1; i <= N; i++)
	{
		cout << result[i] << "\n";
	}

	return 0;
}