# Tutorial A starting point for first-time Pytra users. ## Get Running in 3 Minutes ```python def add(a: int, b: int) -> int: return a + b if __name__ == "__main__": print(add(3, 4)) ``` Transpile this `add.py` to C++ and run it: ```bash ./pytra add.py --output-dir out/add_case --build --run --exe add.out ``` Output: ```text 7 ``` ## Reading Order 1. [How to use](./how-to-use.md) — Build steps, supported languages, main options 2. [Try the samples](./samples.md) — Try the 18 sample programs 3. [Differences from Python](./python-differences.md) — Type annotations, imports, unsupported syntax 4. [Troubleshooting](./troubleshooting.md) — When you get stuck 5. [Exception handling](./exception.md) — raise / try / except / finally 6. [Traits (interfaces)](./trait.md) — Attaching multiple behavioral contracts to a type 7. [Union types and isinstance narrowing](./union-and-narrowing.md) — Handling multiple types and automatic type refinement 8. [Available modules](./modules.md) — Commonly used modules and functions 9. [Architecture](./architecture.md) — Pipeline overview and the role of each stage