Overview

We implement the game Sudoku including:

• A solver.

• A board generator.

• A high score system based on time taken to complete a game.

• A hint system

  • Hint system uses non-backtracking sudoku solvers to guarantee the hint is something a perfect player could come up with, with the info already on the board
  • Hint system also explain what information a player would look at to arrive at the move being hinted.
  • If no determinate moves can be found, hint system recommends guesses with the least variability.
  • For details of the algorithm used by our hint system (see linked paper).

• Functionality to save and load boards, of the users desired difficulty.

• We offer two different ways to play the game:

  • through a command line interface (CLI).
  • through a web server built in Dream. Has a few additional features:
    • visual representations of the information given in each hint
    • the ability to interact with the game through both clicking and keyboard input
    • the visible timer and the ability to pause the game when needed.

Installation and Usage

• Given opam and ocaml version 5.0.0, running the following installs all required packages: opam install . --deps-only --working-dir

• How to run (web server): dune exec server/server.exe

• How to play on web server:

  • Click on a square on the board to highlight it, then click on the number board below the main game to add a number
  • Alternatively, move the highlighted square with arrow keys and input numbers with 1-9 on the keyboard (or try to delete with backspace)
  • Upon completing a game, enter the game name using the text prompt to record the score.
  • Use the buttons on the side to get hints, create a new game or pause the game.

• How to run (CLI): dune exec cli/sudoku.exe [COMMAND] [OPTIONS]

• List of CLI commands with options:

  • init [DIFFICULTY] NAME
    • creates a new game with the given NAME, optionally takes an integer 1-70 determining how difficult the game will be (higher means more difficult)
    • prints the newly created board
  • move VALUE ROW COL
    • tries to place value at the specified row and column
    • if move is valid, updates the board and prints the new one
    • if move is invalid, tells the user why
  • remove ROW COL
    • tries to remove the value at the specified row and column
    • if cell is not fixed, updates the board and prints the new one
    • otherwise, tells the user that is invalid
  • hint
    • gives the user a hint. This can be either:
      • telling the user there is a mistake somewhere (board is no longer solvable)
      • telling the user to make a guess
      • telling the user a suggested move
        • suggested moves are always logically reachable and don't require guessing to reach them.
        • suggested moves also include a short explanation of how that move can be arrived at logically
  • solve
    • solves the board and prints the solution for the user
  • scores
    • prints a list of high scores (name of the game and the time taken)
    • also prints the most recent score
  • print
    • prints the current board
  • list
    • prints the list of currently available games
  • load NAME
    • loads the game with NAME, so any moves, hints etc are now done on the loaded board.
    • to go back to the previous game, need to call load again

Further resources

See Wikipedia for a description of the game.