Solution: Lowest Common Ancestor of a Binary Tree III

Explore the two-pointer approach to find the lowest common ancestor of two nodes in a binary tree when only parent references are available. Learn how this method ensures both pointers traverse equal paths, allowing you to identify their common ancestor without extra space. Understand the time and space complexity for efficient problem solving.

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Statement
Solution
- Time complexity
- Space complexity

Statement

You are given two nodes, p and q. The task is to return their lowest common ancestor (LCA). Both nodes have a reference to their parent node. The tree’s root is not provided; you must use the parent pointers to find the nodes’ common ancestor.

Note: The lowest common ancestor of two nodes, p and q, is the lowest node in the binary tree, with both p and q as descendants.
In a tree, a descendant of a node is any node reachable by following edges downward from that node, including the node itself.

Constraints:

$-10^4 \leq$ ...