Lowest Common Ancestor in Tree | Dataford Interview Questions

Find the lowest common ancestor in a binary tree.

Represent each node as [value, left, right], where a missing child is None. Implement lowest_common_ancestor(root, p, q) to return the value of the lowest node that is an ancestor of both target values. All node values are unique, and both targets are guaranteed to exist in the tree.

Constraints

1 <= number of nodes <= 1000
Node values are unique integers
Both target values exist in the tree
p and q may be located in the same or different subtrees
The tree may be unbalanced

Function Signature

def lowest_common_ancestor(root, p, q):

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Problem

Find the lowest common ancestor in a binary tree.

Constraints

1 <= number of nodes <= 1000
Node values are unique integers
Both target values exist in the tree
p and q may be located in the same or different subtrees
The tree may be unbalanced

Function Signature

def lowest_common_ancestor(root, p, q):

Your question is Lowest Common Ancestor in Tree. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.