Problemset 4 - HW1 (DFS)

import java.util.ArrayList;
import java.util.Scanner;

public class HW1 {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        ArrayList<Node> nodes = new ArrayList<>();
        for(int i = 0; i<n; i++){
            nodes.add(new Node());
        }
        for(int i = 0; i<n-1; i++){
            int a = sc.nextInt()-1;
            int b = sc.nextInt()-1;
            nodes.get(a).arc.add(nodes.get(b));
            nodes.get(b).arc.add(nodes.get(a));
        }
        DFS(nodes.get(0));
        for(Node node: nodes){
            System.out.print(node.dis + " ");
        }
    }
    public static void DFS(Node cur){
        cur.visited = true;
        for(Node next: cur.arc){
            if(!next.visited){
                DFS(next);
                if(cur.dis<next.dis+1){
                    cur.dis = next.dis+1;
                }
            }
        }
    }
}
class Node{
    boolean visited;
    ArrayList<Node> arc;
    int dis;
    Node(){
        visited = false;
        arc = new ArrayList<>();
        dis = 0;
    }
}