Cryptarithmetic Puzzle Solver Streamlit App

Github: Repository.

Introduction

A Streamlit application designed to solve cryptarithmetic puzzles. Cryptarithmetic puzzles are a type of mathematical game where the digits are replaced by letters. Each letter represents a unique digit, and the goal is to find the digit each letter represents such that the given equation holds true.

Ⅰ. Application Overview

The Cryptarithmetic Puzzle Solver app provides an interactive platform where users can input a cryptarithmetic puzzle and receive a solution. The application uses the simpleai library's constraint satisfaction problem (CSP) solver to find a valid solution for the input puzzle.

Key Features

• User Input for Puzzle Words: Users can enter three words representing the cryptarithmetic puzzle. The app is designed to solve puzzles in the format of "WORD1 + WORD2 = WORD3".

• Constraint Satisfaction Problem Solving: The app employs the CSP solving technique to find a solution that satisfies all constraints, including unique digit representation and correct arithmetic calculation.

• Solution Display: If a solution exists, the app displays the original words with letters replaced by the corresponding digits, demonstrating the valid arithmetic operation.

Ⅱ. How It Works

1. Defining Constraints: Two primary constraints are defined:

   • constraint_unique: Ensures all letters represent unique digits.
   • constraint_problem: Validates the arithmetic equation by converting letters to digits and checking if the sum is correct, including the condition that the first letter of any word cannot represent zero.

2. Streamlit Interface:

   • Page Configuration: Set with a puzzle-themed title and icon.
   • User Input: Users input the three words of the puzzle in designated text fields.
   • Solution Process: Upon clicking the 'Solve' button, the app processes the input, applies CSP with backtracking to find a solution, and displays the outcome in the output column.

Ⅲ. Implementation Details

• The simpleai.search.CspProblem and backtrack function are used to define and solve the puzzle.
• The puzzle words are processed to identify unique letters, which serve as variables in the CSP.
• Domains for each variable are digits from 0 to 9, with constraints applied to ensure a valid and unique solution.
• The solution, if found, is displayed by mapping each letter to its corresponding digit, showing both the original and solved equations.

Ⅳ. Solution Display

• Successful Solution: The app shows the original words with their corresponding numeric values, illustrating how the puzzle's equation holds true with the found digit substitutions.
• No Solution: In cases where no solution exists given the constraints, the app informs the user that no solution can be found.

Ⅴ. Conclusion

The Cryptarithmetic Puzzle Solver Streamlit app is an engaging tool that combines the fun of puzzle-solving with the power of programming and artificial intelligence. By leveraging CSP and backtracking algorithms, it offers an automated solution to what is traditionally a manually intensive puzzle type. This app demonstrates the practical application of AI techniques in recreational mathematics and provides a user-friendly interface for puzzle enthusiasts to test and solve cryptarithmetic challenges.