BoltBait's Sudoku Game

How to use the sudoku software

When a puzzle is presented to you, the board is mostly empty. You need to "SET" a digit (shown in black) in all of these empty cells to solve the puzzle. The digits in blue are the starting clues. The blue digits, called "Given" digits can not be changed.

If you've never solved a sudoku puzzle before, I can show you how to solve a sudoku puzzle. Go read that page and come back when you're ready. I'll wait.

OK, ready to learn this specific program? Let's begin!

Selecting Cells

In order to change the contents of a cell, you must first select it. You can select cells in various ways:

1) Click on a cell to select it. Your selection is shown with a yellow/gold background:

2) Click and drag to select multiple adjcent cells:

3) Shift-click to extend your current selection

4) Alt-Click a cell to remove it from your current selection

5) Use one of the onscreen select buttons:

The "G" button adds all Given and Set cells to your current selection.

The "double arrow" button inverts your current selection:

Once you have one or more cells selected, you can modify them in various ways:

Setting Digits

This is the whole point of the game, to set digits in every cell! Select a cell and click one of the "Set" numbers to place number into your solution:

Pencil Marks

One common technique to solving sudoku puzzles is to use pencil marks when you're trying to decide between two or three numbers that go into a cell.

Select one or more cells and then click one of the "Pencil mark" numbers to toggle the desired pencil mark within the selected cells.

If a cell doesn't have the selected number, it will be added to the cell's current pencil marks. If the cell already has the number in it, it will be removed:

You can not pencil mark a cell that already has a Given digit or a Set digit in it.

Delete and Undo

The delete button contains a red "X" and the undo button is a curved arrow pointing left.

Pressing the delete ("X") button clears out any Set digits or Pencil marks from a cell.

As you solve a sudoku puzzle, all moves you make are stored in a history list. At any time you feel you've made a mistake, you can step backwards through the history by pressing the Undo button.

Be careful though as you can not step forward if you step backward too far!

Background Coloring

Some advanced solving techniques require marking cells in the grid for future reference. Non marked cells have a white background. You can mark cells using red or blue by using the following buttons:

If a cell is marked in both blue and red, it becomes purple! So, that gives you three colors to use for marking.

Dark Mode

I, personally, am a huge fan of dark mode in applications. But, I know that sudoku puzzles printed in newspapers or books are shown with a white background. Therefore, the choice is up to you. If you want to solve your sudoku puzzles on a darker background, just click the check box and the colors will change instantly.

The cell coloring is slightly different based on the coloring mode. Here's what the different modes look like:

New Game

If you get stuck, want to start a different puzzle, or simply want to return the main menu, click the "New game" link.

You will be prompted to make sure you really want to abandon the current puzzle. Answer carefully, this can not be undone!

Clicking "Yes" sends you to the main menu. Clicking "No" returns you to the current puzzle.

Winning the Game

Once you have "Set" a digit in every cell of the grid, as long as there are no invalid numbers, you win the game. Here is an example of a completed puzzle:

Once you complete a puzzle, your solve time is recorded and you will see a quick animation followed by a prompt to see what you want to do next:

Clicking "Yes" will take you back to the main menu. Clicking "No" will close the program. Clicking "Cancel" will allow you to see the animation again.

Keyboard Controls

While a mouse (or other pointer) is required to select cells, most other functions within the program can be controlled with the keyboard.

Key	Function
I	Invert selection
G	Add all Given and Set cells to selection
Del	Delete cell contents
Ctrl-Z	Undo
R	Color cells Red
B	Color cells Blue
W	Remove color from cells
Alt-D	Toggle Dark Mode
E	Highlight error cells
Alt-N	New Game
F1	Help
Alt-F4	Exit program

The number keys 1-9 are used to either set a digit or to toggle a pencil mark.

- If a single cell is selected, pressing a number will Set that digit into the selected cell.

- If more than one cell is selected, pressing a number will toggle the pencil mark in the selected cells for that number.

If you have more than one cell selected and want to Set a digit into all those cells at once, just use the on-screen buttons!

History

Once you have solved a few puzzles, be sure to click the History button on the main menu screen. It will show you some graphs on how many puzzles you've solved and how long it typically takes you:

You can then click on the various tabs to see the specific data behind each of the graphs.

The Index column shows you the specific puzzle you solved within that level.

What's Next?

- Show me how to solve a sudoku puzzle
- Quick Start Guide
- Visit the Sudoku Home Page to download the Window's application

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