Same Tree

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

Output: true

Both trees have identical structure and values at every node.

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

Output: false

The left subtree of p has a node with value 2, but the left subtree of q is empty. The structures differ.

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

Output: false

Although both trees have the same structure, the values at corresponding positions differ (left child is 2 vs 1, right child is 1 vs 2).

Problem