moveworks·Software Engineer·Technical Phone Screen·Intermediate

Intermediate

Apr 2026

Summary

Moveworks SWE interview with a pretty gnarly string manipulation problem. The question had multiple layered steps and I spent a good chunk of time just making sure I understood what was actually being asked before writing a single line.

Questions Asked (1)

Given a list of strings, find the character(s) with the highest frequency in each string (including ties), compute the proportion of those characters relative to the string length, identify the strings with the lowest proportion, then remove from each of those strings any character that appears in any other string in the original list. Concatenate what remains and return it.

Algorithms & Data StructuresTechnical Trade-offs

Author's notes

This took me a few minutes just to parse.

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AI HintsAI Generated

Suggested Approach

Break the problem into clear sub-tasks: compute character frequencies per string, identify the max frequency and proportion, find the minimum proportion, then perform the removal and concatenation. Discuss the algorithm's time and space complexity and consider edge cases like empty strings or ties. Optionally, mention how you would test the solution.

Pro tip: Clarify assumptions upfront, such as whether the removal applies only to the selected strings and whether characters are case-sensitive. This shows attention to detail and prevents misinterpretation.

1. Clarify and Restate

Confirm the problem requirements and edge cases with the interviewer, restating the goal in your own words to ensure alignment.

2. Compute Frequencies and Proportions

For each string, count character frequencies, find the maximum frequency, and compute the proportion (max frequency / string length). Handle ties by considering all characters with that max frequency.

3. Identify Strings with Lowest Proportion

Determine the minimum proportion across all strings and collect all strings that have that proportion.

4. Remove Characters from Selected Strings

Build a set of all characters that appear in any other string (i.e., any string not in the selected set). For each selected string, remove any character that is in this set.

5. Concatenate and Return

Concatenate the remaining characters from the selected strings in their original order and return the result. Discuss complexity and potential optimizations.

Key Points to Mention

Time and space complexity analysis (e.g., O(N * L) where N is number of strings and L is average length).
Handling ties for highest frequency characters within a string.
Edge cases: empty strings, strings with all unique characters, multiple strings with the same minimum proportion.
Efficient data structures: hash maps for frequency counting, sets for character removal.
Testing strategy: unit tests for each step and integration tests for the overall function.
Trade-offs between different approaches (e.g., precomputing global character set vs. on-the-fly removal).

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.