#6 most askedVery commonMediumBST
Lowest Common Ancestor of a BST
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🏢 Asked in real interviews
No reports yet. Were you asked this? Be the first to say where.In a BST, return the value of the lowest node that has both p and q (values) as descendants. A node counts as its own descendant.
BST [6, 2, 8, 0, 4, 7, 9], p = 2, q = 8 → 6; p = 2, q = 4 → 2.
🧪 Practice
Write your solution, then press Run tests. Explain your approach out loud as you go.
def lca_bst(root, p, q):
pass
Output appears here. Press Run or Ctrl/⌘ + Enter.
Try it first. Struggling for a few minutes is how it sticks.