Lowest Common Ancestor in Binary Tree | Dataford Interview Questions

Lowest Common Ancestor of a Binary Tree (LeetCode 236)

Asked in the Round 1 DSA stage. Given a binary tree with unique integer values and two existing node values p and q, return the value of their lowest common ancestor.

The tree is represented by nested dictionaries: {"val": number, "left": node_or_null, "right": node_or_null}. Implement lowest_common_ancestor(root, p, q).

Constraints

1 <= number of nodes <= 10^5
Node values are unique integers
p and q exist in the tree
p and q are different

Function Signature

def lowest_common_ancestor(root, p, q):

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