filter elements from array core interview pattern Pattern
1 problems
Pattern pages help build reusable solving frames. Identify signals first, then explain state, transition, and edge handling.
Recognition Signals
- Tests knowledge of JavaScript's `filter()` method and custom function behavior.
- Checks understanding of handling edge cases like empty arrays or non-truthy values.
Solve Flow
- 1. Define the active state/window.
- 2. Update state while preserving invariants.
- 3. Validate with edge-heavy examples.
Common Misses
- Not handling edge cases like an empty array or invalid return values from the filtering function.