---
name: calculator
description: Build a simple calculator with basic arithmetic operations.
---
# Calculator Project

Create a command-line calculator that supports basic arithmetic.

## Requirements

- Support addition, subtraction, multiplication, and division
- Read expressions from stdin, one per line
- Print the result to stdout
- Handle division by zero with an error message
- Exit on empty input or EOF

## Example

```
> 2 + 3
5
> 10 / 0
Error: division by zero
> 7 * 6
42
```

## Implementation

Use the language best suited to the project. Keep it simple — no external dependencies.
