Welcome to the "Build Your Own Calculator" challenge! This project is an opportunity to create a calculator that can parse and compute mathematical expressions. You can choose to build it as a command-line tool, a desktop application, or a web-based application. By completing this challenge, you will get hands-on experience with parsing algorithms and the stack data structure in a real-world application.
Before diving into the code, set up your development environment:
- Choose your target platform (CLI, desktop, or web).
- Select your IDE/editor.
- Pick a programming language.
Prepare your environment to begin developing and testing your solution.
Your first goal is to parse and compute four basic arithmetic operations:
- Addition (
1 + 2) - Subtraction (
2 - 1) - Multiplication (
2 * 3) - Division (
3 / 2)
Ensure your calculator can handle these inputs and return the correct answer, accounting for both integer and floating-point operations. Be mindful of potential invalid inputs.
Testing Tip: When testing multiplication in the shell, quote the expression to prevent character expansion (e.g., calc '2 * 3' should return 6).
Before proceeding, decide whether to start coding for Step 1 immediately, potentially using test-driven development (TDD), or to read through all the steps first, which might influence your approach. Choose your adventure!
Expand your calculator's capabilities to parse and compute more complex expressions involving precedence and parentheses, such as 1 + 1 * 5 and (1 + 1) * 5.
A powerful method for dealing with complex expressions is converting infix notation to postfix notation (reverse polish notation). This conversion simplifies the computation of expressions with precedence and parentheses.
- Basic Example:
(1 * 2) - (3 * 4)in postfix notation is1 2 * 3 4 * -. - Use the shunting yard algorithm for parsing expressions into postfix notation, leveraging a stack for efficient computation.
Finally, enhance your calculator to handle even more complex expressions. This step encourages creativity in generating test cases and implementing features such as:
- Brackets for precedence.
- Advanced mathematical functions like
sin,cos, andtan.
Develop automated tests for your calculator to ensure accuracy and reliability. Test a variety of expressions to cover basic and advanced scenarios.
Completing this challenge will deepen your understanding of parsing algorithms, the stack data structure, and test-driven development. It's a valuable opportunity to apply theoretical knowledge to a practical project. Good luck, and have fun coding your own calculator!