#235

Lowest Common Ancestor of a Binary Search Tree

medium· Treesruns: 0

Given a binary search tree, find the lowest common ancestor (LCA) of two given nodes p and q in the BST. The LCA is the lowest node in the tree that has both p and q as descendants, where a node can be a descendant of itself.

wpm 0acc 100%time 0:000 / 403

class Solution:
    def lowestCommonAncestor(
        self, root: TreeNode, p: TreeNode, q: TreeNode
    ) -> TreeNode:
        curr = root
        while curr:
            if p.val < curr.val and q.val < curr.val:
                curr = curr.left
            elif p.val > curr.val and q.val > curr.val:
                curr = curr.right
            else:
                return curr
        return root

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