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).”



Note: Use the fact that it is a Binary Search Tree, and not just any Binary Tree


def lowestCommonAncestor(root: 'TreeNode', p: 'TreeNode', q: 'TreeNode'):
       
    if p.val < root.val and q.val < root.val:
        return lowestCommonAncestor(root.left, p, q)
    elif p.val > root.val and q.val > root.val:
        return lowestCommonAncestor(root.right, p, q)
    return root

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