Turner & Townsend backend technical assessment

This repository contains my solutions to the Turner & Townsend backend technical assessment. While the brief requested solving only one problem, I started with the "spiciest" Stack task for the first hour and then tackled the other two tasks in the second hour. I did come back the next day and spend some extra time improving the README documentation.

Solutions

Stack Calculator

Complexity: Medium

A stack-based programming language interpreter (Fifth) that supports arithmetic operations and stack manipulation commands. Features an interactive REPL with comprehensive error handling.

Roman Numerals Converter

Complexity: Medium

Converts Roman numerals to Arabic numbers using additive logic. Includes flexible input handling with case-insensitive processing and automatic filtering of invalid characters.

Collatz Conjecture Calculator

Complexity: Low

Calculates the number of steps in the Collatz sequence (3n + 1 problem) with step-by-step visualization. Demonstrates mathematical algorithm implementation with interactive feedback.

Architecture

All three solutions follow consistent design principles:

• Class-based structure for encapsulation and testability
• Interactive command-line interfaces with graceful error handling
• Comprehensive test suites with good coverage
• Modern Python features and best practices

Quick Start

Requirements: Python 3.10+, pytest

# Install dependencies
pip install -r requirements.txt

# Run solutions
cd stack && python stack.py
cd roman && python roman.py
cd collatz && python collatz.py

# Run tests
pytest                    # All tests
pytest stack/            # Individual solution tests

Click the links above to view detailed documentation for each solution.