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


  1. The number of nodes in the tree will be between 2 and 100.
  2. Each node has a unique integer value from 1 to 100.

* Images Source : LeetCode


Here we can perform level order traversal to check if x and y are at the same depth, at the same time check if parent of the both the elements is same.


We encourage you to write a comment if you have a better solution or having any doubt on the above topic.

Leave a Reply

Your email address will not be published. Required fields are marked *