alexey3250 / ai50-projects-2020-x-knights

Knights and Knaves Puzzle Solver

This project uses the power of propositional logic and a model checking algorithm to solve a set of logic puzzles famously known as "Knights and Knaves" puzzles. The concept originates from Raymond Smullyan's 1978 book, “What is the name of this book?”

Background

In Knights and Knaves puzzles, each character is either a knight or a knave. Knights always tell the truth, while knaves always lie. The challenge is to determine, given a set of sentences spoken by each of the characters, whether each character is a knight or a knave.

Structure

The project comprises two Python files:

1. logic.py: This script defines classes for different types of logical connectives and includes a function called model_check which verifies if a query logically follows from a given knowledge base.

2. puzzle.py: This script sets up the logical framework for each puzzle. Here, we define our knowledge base for each puzzle and use model checking to compute whether each character is a knight or a knave.

Puzzles

The project includes solutions for four different puzzles:

1. Puzzle 0: A single character, A, states “I am both a knight and a knave.”

2. Puzzle 1: Character A says “We are both knaves.” and character B says nothing.

3. Puzzle 2: Character A says “We are the same kind.” and character B says “We are of different kinds.”

4. Puzzle 3: Character A says either “I am a knight.” or “I am a knave.” (it's unknown which). Character B says “A said ‘I am a knave.’” and then “C is a knave.” Character C says “A is a knight.”

Usage

To use this puzzle solver, clone the repository and run the puzzle.py script. It will print out the solutions for the puzzles by determining whether each character is a knight or a knave.

python puzzle.py

License

This project is licensed under the terms of the MIT license.