package com.company;

import java.util.*;

public class Main {

    private static Object[] BFS(Node goal, Node start) {
        Queue<Node> q = new ArrayDeque<>();
        ArrayList<Node> discovered = new ArrayList<>();

        q.add(start);

        while(!q.isEmpty()) {
            Node v = q.poll();
            discovered.add(v);

            if(v == goal) {
                return discovered.toArray();
            }

            for (Node neighbor:
                 v.getNeighbors()) {
                q.add(neighbor);
            }
        }

        return discovered.toArray();
    }

    public static void main(String[] args) {
        // write your code here
        Node root = new Node(0);
        Node child1 = new Node(1);
        Node child2 = new Node(2);
        Node grandchild = new Node(3);
        root.addNeighbor(child1);
        root.addNeighbor(child2);
        child2.addNeighbor(grandchild);

        for (Object v:
             BFS(grandchild, root)) {
            Node casted = (Node)v;
            System.out.print(casted.getValue() + " ");
        }
    }
}