#93 Lowest Common Ancestor in a Binary Tree

Companies:

Yandex

Themes:

AlgorithmsTreesPractice

A class representing a binary-tree node is given:

public class TreeNode {
    TreeNode parent;
    TreeNode left;
    TreeNode right;
}

Implement the getLowestCommonParent(TreeNode first, TreeNode second) method, which finds the lowest common ancestor (LCA) of two specified nodes in a binary tree.

The method must use O(1) memory, meaning that additional data structures such as collections, arrays, and so on cannot be used.

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