Maximize Unique Characters
mediumMulti-file Python Guided available Pro
A DSA drill: pick a character-disjoint subset of strings that maximizes the total distinct characters used. Implement an exact bitmask and DFS search and pass the real pytest suite.
Choose how you want to solve it
Both modes open the same in-browser IDE with the AI pair programmer and the real test suite.
Recommended
Guided Walkthrough
A phase-by-phase interview simulation with instant feedback on your reasoning.
- Explain decisions by voice or text
- Focused, phase-scoped test runs
- Progressive hints when stuck
- Full solution walkthrough at the end
Sandbox
The open coding view. No phases, just you and the codebase.
- Full instructions up front
- Free-form AI pair-programmer
- Run the entire test suite anytime
This problem requires a paid plan. You can preview the statement for free.