Solution: Lowest Common Ancestor of a Binary Tree

Explore how to determine the lowest common ancestor of two nodes in a binary tree using a depth-first search traversal. Understand the recursive technique that checks each node and how tracking variables help identify the ancestor efficiently. This lesson helps you master tree traversal and ancestor identification to solve common binary tree problems.

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Statement
Solution

Statement

Given the root node of a binary tree with $n$ nodes, your task is to find the lowest common ancestor of two of its nodes, p and q.

Note: The lowest common ancestor of two nodes, p and q, is defined as the lowest node in the binary tree that has both p and q as descendants.

A node can also be a descendant of itself. For example, if q is a descendant of p, and we know that p is a descendant of itself, then p will be the lowest common ancestor of p and q.

Constraints:

$2 \leq n \leq 500$

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