[백준 1260] DFS와 BFS - 인접 리스트 이용

[백준 1260] DFS와 BFS

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

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Scanner;
 
public class Main {
    
    public static void dfs(ArrayList[] a, boolean[] c, int v) {
        
        if(c[v]) return;
        
        c[v] = true;
        System.out.print(v + " ");
        
        for (int vv : a[v]) {
            if(!c[vv]) {
                dfs(a,c,vv);
            }
        }
    }
    
    public static void bfs(ArrayList[] a, boolean[] c, int v) {
        Queue q = new LinkedList<>();
        
        q.add(v);
        c[v] = true;
        
        while(!q.isEmpty()) {
            v = q.poll();
            System.out.print(v + " ");
            
            for(int vv : a[v]) {
                if(!c[vv]) {
                    q.add(vv);
                    c[vv] = true;
                }
            }
        }
        
    }
    
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        
        int n = sc.nextInt();
        int m = sc.nextInt();
        int v = sc.nextInt();
        
        ArrayList[] a = (ArrayList[]) new ArrayList[n+1];
        
        for (int i = 0; i <= n; i++) {
            a[i] = new ArrayList<>();
        }
        
        boolean[] c = new boolean[n+1];
        
        for (int i = 0; i < m; i++) {
            int v1 = sc.nextInt();
            int v2 = sc.nextInt();
            
            a[v1].add(v2);
            a[v2].add(v1);
        }
        
        for (int i = 1; i <= n; i++) {
            Collections.sort(a[i]);
        }
        
        dfs(a, c, v);
        System.out.println();
        Arrays.fill(c, false);
        bfs(a, c, v);
    }
 
}