Implement Spreadsheet Cells with Dependencies
Company: Ramp
Role: Software Engineer
Category: Software Engineering Fundamentals
Difficulty: medium
Interview Round: Technical Screen
Design spreadsheet-like `get` and `set` operations for cells where formulas can depend on other cells. When a cell changes, dependent cells should reflect the new value. Explain how you would represent dependencies and update them correctly.
### Constraints & Assumptions
- Cells are identified by string names such as A1.
- A cell can contain either a literal value or a formula referencing other cells.
- Formula parsing can be simplified to dependencies plus an evaluation function.
- Cycles should be detected or rejected.
### Clarifying Questions to Ask
- Are formulas limited to sums or arbitrary expressions?
- Should values update eagerly on set or lazily on get?
- How should cycles be reported?
- Can a formula's dependency list change on update?
- How many cells and dependencies are expected?
### What a Strong Answer Covers
```premium-lock What a Strong Answer Covers
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### Follow-up Questions
- How would you support ranges like A1:A10?
- How would you make recalculation incremental?
- How would you cache values safely?
- How would concurrent edits change the design?
Quick Answer: This Ramp software engineering question tests spreadsheet cell dependencies, recalculation order, and cycle handling. It is useful preparation for interviews that combine graph traversal, incremental updates, and product-like edge cases in a compact coding design.