Solution: Lowest Common Ancestor of a Binary Tree

Explore how to find the lowest common ancestor of two nodes in a binary tree by using a depth-first search approach. Understand the recursive algorithm that tracks nodes found in subtrees and applies logic to determine the ancestor efficiently. This lesson helps you implement and optimize solutions for binary tree ancestor 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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