Lesson 52 of 55
12 mins readPython Comprehensive Functional Practice Challenges
In Plain English
Tackle practical challenges integrating pattern matching, custom ADTs, Functor/Applicative transformations, and tail-recursive algorithms.
Deep Dive: How It Works
Problem 1: Run-Length Encoding and Decoding on homogeneous lists.
Problem 2: Pure State evaluation of a Reverse Polish Notation (RPN) calculator.
Problem 3: Tree depth and tree map operations over recursive ADTs.
Core Rules to Remember
Multi-Concept Integration: Combine pure recursion, pattern matching, and typeclass instances.
Idiomatic Haskell Patterns: Point-free pipelines and zero-mutation data transformation.
Live Interactive Example
Hit Run Code to see it liveReverse Polish Notation (RPN) Calculator
Python 3.12
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Output Console
Click "Run Code" to view the rendered output.
How it works: The pure stack fold evaluated the postfix expression.
Your Turn: Micro Challenge
No pressure! Edit the starter code below and test your solution with instant feedback.
Micro Exercise
Run Simple RPN Expression
- Evaluate `solveRPN "3 4 + 2 *"` (which is `(3 + 4) * 2 = 14.0`).
- Print `"RPN Result: "` followed by `show res`.
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Sandbox Output
Click "Run & Check" to test your solution.
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