Sudoku Solver

A TypeScript library for solving and generating Sudoku puzzles.

Installation

npm install @pipags/sudoku-solver

Usage

import { Sudoku, Generator } from '@pipags/sudoku-solver';

// Create a new Sudoku puzzle
const generator = new Generator();
const result = generator.generateSudoku('easy');

// result contains: { id: string, puzzle: number[][], solution: number[][] }
console.log('Puzzle:', result.puzzle);
console.log('Solution:', result.solution);
console.log('ID:', result.id); // ID is in base64url format

// Solve the puzzle
const sudoku = new Sudoku(result.puzzle);
const solution = sudoku.getSolution();
console.log('Solved:', solution);

Features

• Solve any valid Sudoku puzzle
• Generate new puzzles with different difficulty levels:
  • Easy
  • Medium
  • Hard
  • Extreme
• TypeScript support with type definitions
• 100% test coverage
• Generate unique IDs in base64url format for each puzzle

API

Sudoku Class

class Sudoku {
  constructor(grid: number[][]);
  isValid(row: number, col: number, num: number): boolean;
  solve(): boolean;
  getSolution(): number[][];
}

Generator Class

class Generator {
  generateSudoku(difficulty: 'easy' | 'medium' | 'hard' | 'extreme'): { id: string, puzzle: number[][], solution: number[][] };
  generateFromId(id: string, difficulty?: 'easy' | 'medium' | 'hard' | 'extreme'): { id: string, puzzle: number[][], solution: number[][] };
  generateMultipleSudoku(count: number, difficulty?: 'easy' | 'medium' | 'hard' | 'extreme'): { id: string, puzzle: number[][], solution: number[][] }[];
}

Project Structure

• src/index.ts - exports library components
• src/sudoku.ts - Sudoku solving logic
• src/generator.ts - puzzle generator
• src/examples.ts - usage examples

How it Works

Uses backtracking to solve Sudoku puzzles:

1. Find empty cell
2. Try numbers 1-9
3. Check row, column and box
4. Move to next cell if valid
5. Backtrack if stuck

License

MIT

Project Structure

• src/index.ts - exports library components
• src/sudoku.ts - Sudoku solving logic
• src/generator.ts - puzzle generator
• src/examples.ts - usage examples

How it Works

Uses backtracking to solve Sudoku puzzles:

1. Find empty cell
2. Try numbers 1-9
3. Check row, column and box
4. Move to next cell if valid
5. Backtrack if stuck