Tree #01
Medium Lowest Common Ancestor of a Binary Tree
Find the lowest node in a binary tree whose subtree contains both target nodes.
Solved treedfslowest common ancestor
Tree
Recursive structure, subtree information, and ancestor-style reasoning. The focus here is postorder recursion and tree invariants. Official LeetCode problems are linked on every page instead of being mirrored here.
1 published solutions
3 distinct tags
0 easy / 1 medium / 0 hard difficulty mix
May 21, 2026 most recently updated page
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