Find Words That Contain Other Words as Substrings
Given a list of words, implement a function that returns all words containing other words from the list as substrings. For example, given ['apple', 'app', 'banana', 'nana'], return ['apple', 'banana'] since 'apple' contains 'app' and 'banana' contains 'nana'.
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Meta
Guided Practice
Practice Word Container with AI-powered feedback
Guided Practice
Practice Word Container with AI-powered feedback
Hello Interview Problem Breakdown
Word Container
A detailed walkthrough of the Word Container problem, covering the approach, implementation, and optimization.
Question Timeline
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Mid May, 2026
Meta
Senior
Like others reported. It's an open-ended question. The interviewer wanted to see how you'd approach and breakdown the problem. I started by explaining the limitation and point of improvement for the existing brute force solution. Then the interviewer asked me if I can optimize it. I opted-in to brainstorm with AI at this moment (Not sure if that's the right timing though). A benchmark was provided and was run against my two other optimizations, Hashset for substrings and Trie. The interviewer asked me if I can optimized the two solutions further, either by merging lines of code or variables.
Late April, 2026
Meta
Senior
The problem's core was exactly the same! Had to find the container words. The focus is not on the best solution, but how you articulate your thoughts, keep the interviewer in the loop, and start with first iteration of improvement - that will improve the benchmarks. A simple sorting with early pruning gave significant improvement for the benchmarks. Just explained Trie by drawing, and the interviewer asked a couple of edge-cases on it.
Early April, 2026
Meta
Manager
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