README: problems solved in Python 🐍

Here I show how I solve some problems that may be used as tests in the recruitment process. I got inspired from this article on RealPython.

Table of contents

• Dear recruiter... 👨‍💻👩‍💻
• The problems 🤔
  • 1_integer_sum.py Sum a range of positive integers
  • 2_caesar.py Encrypt or decrypt a string according to Caesar cipher
  • 3_logparse.py Parse a log and print a report
  • 4_sudoku.py Classical Sudoku solver
• Contributions 🙏
• License 🔖

Dear recruiter... 👨‍💻👩‍💻

I want to show you:

• how I solve problems with Python code (just trust I didn't had a peek at the solution before attempting 😉);
• I know how to style and write readable yet efficient and maintainable code;
• I know how to use Git and GitHub;
• I do have problem-solving skills and I do like solve problems;
• I do have analytical skills (by the way, I'm an engineer);
• I know how to write documentation with the ReStructuredText syntax (which I think is harder than Markdown, but it makes me obtain wonderful results without using LaTeX);
• I know how to use Sphinx and GitHub Actions to automatically build beautiful and professional documentation from docstrings; here it is!
• as you read, I speak (or better, I write) English.

The problems 🤔

Here is a list of all the problems I solved. Each problem is fully contained in a file.

Requirements

Python 3.8.5 and libraries in requirements.txt, to be installed through pip install -r requirements.txt (maybe in a virtual environment).

1_integer_sum.py Sum a range of positive integers

Single function which ingests a number; if it is a positive integer, return the sum of all positive integers from zero to that number included, otherwise returns zero.

2_caesar.py Encrypt or decrypt a string according to Caesar cipher

Encrypt or decrypt a string by shifting the letters of n positions in the alphabet; each non-letter character is preserved as it is.

Three versions are available, increasingly faster and more readable.

3_logparse.py Parse a log and print a report

Parse the test.log file looking for specific strings holding Device status (ON, OFF or ERR); print a report with the total ON time and the timestamps of ERR events.

4_sudoku.py Classical Sudoku solver

Read puzzles from a .sdm file and reports the solutions, if they can be solved with a unique solution. The solution is checked against the one computed with the py-sudoku library.

At present, the algorithm can solve the easiest soduku.

Contributions 🙏

Thank you for help me in improving the solutions! If you have a better solution (faster, cleaner, more explicit, anything else), please open an issue or a pull request, I'll be happy to discuss with you.

Whole new solutions will be added to the existing ones; the author will be named in the docstring (no money, sorry).

Also, if you have any other interesting problem, you're welcome to submit it!

License 🔖

All the material in this repo is available through the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International license.