[백준] 1260번 DFS와 BFS

import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Scanner;

public class Main {
	static ArrayList<Integer>[] adj;
	static boolean[] visit;
	static StringBuilder sb = new StringBuilder();
	
	static void dfs(int x) {
		visit[x] = true;
		sb.append(x).append(' ');
		for(int y: adj[x]) {
			if(visit[y]) continue;
			dfs(y);
		}
	}
	
	static void bfs(int x) {
		Queue<Integer> queue = new LinkedList<>();
		queue.add(x);
		visit[x] = true;
		
		while(!queue.isEmpty()) {
			x = queue.poll();
			sb.append(x).append(' ');
			
			for(int y:adj[x]) {
				if(visit[y]) continue;
				queue.add(y);
				visit[y] = true;
			}
		}
	}
	
	
    public static void main(String[] args) {
    	
    	Scanner kb = new Scanner(System.in);
    	
    	int N = kb.nextInt();
    	int M = kb.nextInt();
    	int V = kb.nextInt();
    	adj = new ArrayList[N+1];
    	
    	for(int i=1; i<=N; i++) {
    		adj[i] = new ArrayList<Integer>();
    	}
    	
    	
    	for(int i=1; i<=M; i++) {
    		int x= kb.nextInt();
    		int y = kb.nextInt();
    		adj[x].add(y);
    		adj[y].add(x);
    	}
    	
    	// 번호가 작은 것부터 방문하기 위해 정렬
    	for(int i=1; i<=N; i++) {
    		Collections.sort(adj[i]);
    	}
    	
    	
    	visit = new boolean[N+1]; // 배열 방문 초기화
    	dfs(V);
    	sb.append('\n');
    	for(int i=1; i<=N; i++) {
    		visit[i] = false;
    	}
    	bfs(V);
    	System.out.println(sb);

    }
}