백준 1260 DFS와 BFS / JAVA

https://www.acmicpc.net/problem/1260

1260번: DFS와 BFS

 

 

 

public class boj_1260_DFSBFS {
	
	static ArrayList<Integer>[] arr;
	static boolean[] visited;
	static int n;
	public static void main(String[] args) throws IOException {
		// TODO Auto-generated method stub
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st = new StringTokenizer(br.readLine());
		
		n = Integer.parseInt(st.nextToken());
		int m = Integer.parseInt(st.nextToken());
		int r = Integer.parseInt(st.nextToken());
		
		arr = new ArrayList[n+1];
		visited = new boolean[n+1];
		
		// list구현
		for(int i = 0; i <=n; i++) {
			arr[i] = new ArrayList<>();
		}
		
		// 그래프구현
		for(int j = 0; j < m; j++) {
			st = new StringTokenizer(br.readLine());
			int a = Integer.parseInt(st.nextToken());
			int b = Integer.parseInt(st.nextToken());
			arr[a].add(b);
			arr[b].add(a);
		}
		
		//오름차순 정렬
		for(int k = 1; k <= n; k++) {
			Collections.sort(arr[k]);
		}
	
		dfs(r);
		System.out.println();
		bfs(r);
	}
	
	public static void dfs(int node) {
		if(visited[node] == true) {
			return;
		} else {
			visited[node] = true;
			System.out.print(node + " ");
			for(int x : arr[node]) {
				if(visited[x] == false) {
					dfs(x);
				}
			}
		}
	}
	
	public static void bfs(int node) {
		Queue<Integer> queue = new LinkedList<>();
		visited = new boolean[n+1];
		visited[node] = true;
		queue.offer(node);
		
		while(!queue.isEmpty()) {
			int now = queue.poll();
			System.out.print(now + " ");
			for(int x : arr[now]) {
				if(visited[x] == false) {
					visited[x] = true;
					queue.offer(x);
				}
			}
		}
	}
}