Leetcode 235. Lowest Common Ancestor of a Binary Search Tree. Python (Easy)

235. Lowest Common Ancestor of a Binary Search Tree

Given a binary search tree (BST), find the lowest common ancestor (LCA) node of two given nodes in the BST.

According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes p and q as the lowest node in T that has both p and q as descendants (where we allow a node to be a descendant of itself).”

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.right
            elif p.val < curr.val and q.val < curr.val:
                curr = curr.left
            else:
                return curr

Explaination :

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