Same Tree🎹

Photo by Serge van Neck on Unsplash

Question

Given the roots of two binary trees p and q, write a function to check if they are the same or not.

Two binary trees are considered the same if they are structurally identical, and the nodes have the same value.

Example 1:

Input: p = [1,2,3], q = [1,2,3]
Output: true

Example 2:

Input: p = [1,2], q = [1,null,2]
Output: false

Example 3:

Input: p = [1,2,1], q = [1,1,2]
Output: false

Constraints:

• The number of nodes in both trees is in the range [0, 100].
• -104 <= Node.val <= 104

Java Solution

O(n)
Where n is the number of nodes in a tree
Ps: in the case of java the n will be the number of nodes in a tree, but the tree which has less number of nodes in it. Because Java does have short circuit evaluation.

Code