Sudoku — CLI & GUI (C / SDL2)

Complete Sudoku application in C with a CLI, SDL2 GUI, multiple solvers, and a generator that enforces uniqueness.

Features

• CLI generate/solve/print with solver selection.
• SDL2 GUI with hint, trace, save/load, undo/redo.
• Solvers: DLX (Algorithm X), backtracking, MRV + bitmask, constraint propagation.
• Benchmark/plots tooling and datasets.

Screenshots

Benchmarks

Requirements

• C compiler with C11 support and make.
• SDL2 + SDL2_ttf (for GUI).
• pkg-config (recommended for SDL2 flags). Note: the GUI bundles DejaVu Sans in assets/fonts/ (see its license file).

On Ubuntu/Debian:

sudo apt-get update
sudo apt-get install -y libsdl2-dev libsdl2-ttf-dev

Build

make cli
make gui
make bench

Tests

make test
BF_TRIALS=200 make test-bf   # heavy brute-force run

CLI usage

./build/sudoku_cli --generate 40 > k40.txt
./build/sudoku_cli --solve k40.txt --solver mrv
./build/sudoku_cli --solve - --solver dlx

--solver accepts: auto, dlx, bt, mrv, cp. --generate <k> expects k in 0..60 for unique puzzles.

Reproducibility

You can fix the RNG seed via env var or CLI:

SEED=123 ./build/sudoku_cli --generate 40 > k40.txt
./build/sudoku_cli --generate 40 --seed 123 > k40.txt

GUI usage

./build/sudoku_gui

Keys: H (hint), S (solve), B (trace), K (save), L (load), N (new).

Project structure

include/            # headers
src/utils/          # grid, io, rand, trace
src/solvers/        # dlx, backtracking, mrv_bitmask, constraint_propagation, rules
src/generator/      # generator
src/interface/      # cli, formatter, save, gui, gui_draw, gui_events, gui_solver
scripts/            # plotting/benchmark helpers
data/               # datasets and save.json
results/            # benchmark outputs
plots/              # generated charts

CLion

Open the folder as a Makefile project (CLion auto-detects Makefile targets).

License

MIT. See LICENSE.