Cousins in Binary Tree

In a binary tree, the root node is at depth 0, and children of each depth k node are at depth k+1.

Two nodes of a binary tree are cousins if they have the same depth, but have different parents.

We are given the root of a binary tree with unique values, and the values x and y of two different nodes in the tree.

Return true if and only if the nodes corresponding to the values x and y are cousins.

Example 1:

Input: root = [1,2,3,4], x = 4, y = 3
Output: false

Example 2:

Input: root = [1,2,3,null,4,null,5], x = 5, y = 4
Output: true

Example 3:

Input: root = [1,2,3,null,4], x = 2, y = 3
Output: false

Constraints:

• The number of nodes in the tree will be between 2 and 100.

• Each node has a unique integer value from 1 to 100.

class Solution {
    public boolean isCousins(TreeNode root, int x, int y) {
        Queue<TreeNode> q = new LinkedList<>();
        q.add(root);
        while (q.size() != 0) {
            boolean xFound = false, yFound = false;
            int size = q.size();
            while (size-- > 0) {
                TreeNode node = q.poll();
                if (node.val == x)
                    xFound = true;
                if (node.val == y)
                    yFound = true;
                if (node.left != null)
                    q.add(node.left);
                if (node.right != null)
                    q.add(node.right);
                // If x and y belong to same parents
                if (node.left != null && node.right != null) {
                    if ((node.left.val == x && node.right.val == y) 
                     || (node.left.val == y && node.right.val == x))
                        return false;
                }
            }
            if (xFound && yFound)
                return true;
        }
        return false;
    }
}