Rational Expression Parser

This project is a parser that recognizes and evaluates arithmetic expressions involving rational numbers. Rational numbers are expressed in the form numerator|denominator, such as 2|3 for two-thirds or 12|5 for twelve-fifths. The parser supports the following operations:

• Addition (+)
• Subtraction (-)
• Multiplication (*)
• Division (/)
• Parentheses for grouping (( and ))

The program reads arithmetic expressions from standard input, evaluates them, and prints the results. If an invalid expression is encountered, the program will terminate and print the number of correctly evaluated expressions before the error.

Installation

1. Clone the repository:

   git clone https://github.com/icorvus/rational-expression-parser.git
   cd rational-expression-parser

2. Create a virtual environment and activate it:

   python3 -m venv venv
   source venv/bin/activate  # On Windows, use `venv\Scripts\activate`

3. Install the dependencies:

   pip install -r requirements.txt

Usage

1. Run the main.py script and provide arithmetic expressions via standard input:

   python main.py

2. Example input:

   2|1+4|1*5|2-18|5
   (2|1+4|1)*5|2-18|5
   four * 5
   

3. Example output:

   42|5
   57|5
   Invalid expression, number of correctly evaluated expressions: 2
   

Code Quality

The code is linted and formatted using ruff, a Python code linter and formatter written in Rust.

To lint and format the code, run:

ruff check .
ruff format .

License

This project is licensed under the MIT License.