import java.util.*;

/**

* Definition for a binary tree node.

* public class TreeNode {

* int val;

* TreeNode left;

* TreeNode right;

* TreeNode() {}

* TreeNode(int val) { this.val = val; }

* TreeNode(int val, TreeNode left, TreeNode right) {

* this.val = val;

* this.left = left;

* this.right = right;

* }

* }

*/

class Solution {

final int NULL_MARKER = Integer.MIN_VALUE;

public boolean isSameTree(TreeNode p, TreeNode q) {

Queue<Integer> OrderP = new ArrayDeque<>();

Queue<Integer> OrderQ = new ArrayDeque<>();

trevasalTree(p, OrderP);

trevasalTree(q, OrderQ);

if (OrderP.size() != OrderQ.size()) return false;

while (!OrderP.isEmpty() && !OrderQ.isEmpty()){

Integer a = OrderP.poll();

Integer b = OrderQ.poll();

if (!a.equals(b)) return false;

}

return OrderP.isEmpty() && OrderQ.isEmpty();

}

public void trevasalTree(TreeNode t, Queue<Integer> queue){

// System.out.print(t.val+ " ");

if (t == null){

queue.add(NULL_MARKER);

return;

}

queue.add(t.val);

trevasalTree(t.left, queue);

trevasalTree(t.right, queue);

}

}