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Expense Ledger

mediumMulti-file Python Guided available Pro

A premium two-module challenge. Parse a freeform ledger of signed transactions, then compute each person's net balance against a 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.

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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
Start guided →
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
Open sandbox →

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