Hybrid Sudoku Engine: Generator & Solver in C++

A robust, lightweight Command Line Interface (CLI) application written in modern C++ that can both generate 100% valid, randomized Sudoku puzzles from scratch and solve any given Sudoku board using a hybrid algorithmic approach.

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🚀 Features

• 100% Valid Puzzle Generation: Automatically creates complete, completely randomized, and mathematically flawless Sudoku boards every single time.
• Dual Input Methods for Solving:
  1. Sequential Mode: Fill the entire board cell-by-cell dynamically.
  2. Index-Based Mode (Recommended): Enter numbers directly by targeting specific row and column indices (1-9), making it incredibly easy to clone a real-world puzzle into the engine.
• Cross-Platform UI Visuals: Uses ANSI escape codes (\033[2J) to clear the terminal screen cleanly for a smooth visual experience during user input and result displaying.
• CMake Build System: Organized cleanly with standard CMakeLists.txt producing two separate executable targets.

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🧠 The Algorithm Behind the Engine

Unlike traditional, rigid deterministic solvers, this project implements a Randomized Brute-Force with Backtracking & Local Row-Reset approach:

• Generation (main.cpp): Fills cells sequentially with valid random numbers (1-9). If it hits a dead-end where a cell cannot legally accept any number (due to row, column, or 3x3 block conflicts) after 150 attempts, it safely resets the entire board state and restarts. This guarantees a uniquely shuffled board layout on every run.
• Solving (solveAlgorithm.cpp): Employs a similar heuristic. It populates empty cells (0) with valid random guesses. If a cell reaches a dead-end (exceeding 250 attempts), the algorithm backtracks by wiping the current row and stepping back to the previous row. If local backtracking cycles too many times (MAX_ROW_RESETS = 5000), it triggers a global reset (goto restart_puzzle) to break out of complex algorithmic traps.

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🛠️ Compilation and Installation

This project uses CMake for easy building. Ensure you have a C++17 compatible compiler (like GCC or Clang) and CMake installed.

1. Clone the Repository

git clone (https://github.com/Wexis39/SudokuAlgorithm.git)
cd SudokuAlgorithm

2. Build via CMake

Create a build directory, generate the build files, and compile the executables:

mkdir build
cd build
cmake ..
cmake --build .

After a successful compilation, you will find two separate executables inside your build directory: sudoku and sudokuSolve.

🎮 How to Use

🎲 1. Generating a Sudoku Board

To generate a completely random and solved Sudoku board, run the generator executable:

Linux/macOS: ./sudoku

Windows: sudoku.exe

🔍 2. Solving a Custom Sudoku Board

To input a puzzle you want the engine to solve, run the solver executable:

Linux/macOS: ./sudokuSolve

Windows: sudokuSolve.exe

📋 How to Input Data in Solver Mode

Upon running, you'll be greeted with a menu:

Option 1 (Sequential): The program asks for numbers for every single cell starting from (0,0) to (8,8). Enter 0 for blank/unknown cells. Type -1 anytime to stop early.

Option 2 (Index-Based - Recommended): Type the Row (1-9), Column (1-9), and the Number. The board will update live on the screen. Once you have populated your starting hints, type -1 during the coordinate entry phase to start the solving engine.

The engine will then process the puzzle and instantaneously print out the final validated Solution block on your screen.

Author

• @Metehan Atalay