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Solution: Lowest Common Ancestor of a Binary Tree

Understand how to implement a recursive depth-first search algorithm to find the lowest common ancestor of two nodes in a binary tree. Explore how tracking nodes in left, right, and current positions helps identify the ancestor efficiently. This lesson helps you solve common tree traversal problems relevant to coding interviews.

Statement

Given the root node of a binary tree with nn 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:

  • 2n5002 \leq n \leq 500
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