Meta Variant for Count Nodes Equal to Average of Subtree (LC2265)
Summary
Shared a solution for a Meta-related problem, LeetCode 2265, and discussed a variant where the task is to determine if every node in a binary tree is the average of its subtree. The problem involves understanding postorder traversal and optimizing it within a short time frame.
Full Experience
Hey y’all! Got another solution for another tagged Meta problem, LeetCode 2265 Count Nodes Equal to Average of Subtree, as well as its variant.
This one’s been asked quite a bit more lately and it’s tripped up a bunch of candidates, and understandably so: deducing postorder traversal and knowing how to manipulate it for optimization in 20 minutes is tricky.
The variant is this: what if you had to return a boolean whether every node in the binary tree is the average of its subtree?
Fyi I've not seen this asked a lot in phone screens but this is speculation from what I've been seeing.
Wishing everyone good luck on their interviews!
Interview Questions (2)
Count Nodes Equal to Average of Subtree
Given a binary tree, the task is to count the number of nodes whose value is equal to the average of the values in their subtree. The solution involves postorder traversal and optimizing the computation of subtree averages efficiently.
Check if All Nodes are Average of Subtree
Variant of the previous problem: determine if every node in the binary tree is the average of its subtree. This requires checking each node's value against the average of its subtree and returning a boolean result.
Preparation Tips
The candidate focused on understanding postorder traversal and optimizing algorithms for binary tree problems, particularly those involving subtree calculations. They likely practiced problems related to tree traversals and subtree properties to handle such questions efficiently during interviews.