Playing Sudoku

The basic rules of Sudoku are easy to explain:

Fill the 9x9 grid with the digits 1 to 9 with respect to the following rule:

Each digit must occur exactly once in each

row,
column and
3x3 sub-grid.

More detailed descriptions may be found e.g. at Wikipedia.

Short introduction on How to play with SUDOKUMAT 5.7

If you have problems or suggestions, let us know:

david.gunkel@gmx.de
m.wegerhoff@gmx.de

Feedback builds the base for further development!

The latest version of SUDOKUMAT is always available at:

http://www.davidgunkel.de

SUDOKUMAT generated puzzles are always unique. Up to level Hard the solution can be found by logic - you don't have to try!

The level Evil is defined by the aspect, that you have to make a decision at least once. For those puzzles SUDOKUMAT shows the minimum number of necessary decisions in the status bar. So beware!

Playing Standard...

Create a new puzzle.
Press the New-Buttons, use the menu File -> New or use the accelertor-key Ctrl. N.
This also starts the timer...
Select a cell
where you want to set a value.
You can do this by either moving the mouse (no click needed!) or use the arrow-keys. The actual position is indicated by the background selected color.
Set a value.
You can simply type a digit or use the mouse-right-click-popup-menu and select a digit or space from there.
Set candidate.
Candidates are set the same way as values, with additionally held Ctrl-key. If you want to enter more than one candidate at a time, you can toggle the mode from value to candidate (or back) by typing a "c", clicking the candidate-button or via menu Mode -> Enter Candidates. By entering its digit a candidate changes state: from unset to set, from set to excluded, or from excluded to unset.
Check solution
When you have filled the last empty cell, SUDOKUMAT will check your solution and tell you whether it is correct or not.

...Beyond...

Undo/Redo
You can do a step-wise undo of the puzzle via Edit -> Undo, a step-wise redo via Edit -> Redo or reset the puzzle to the problem-state via Edit -> Reset, if that seems more attractive to you...
Hint
If you don't see how to proceed - let SUDOKUMAT show you a field, that is suitable for the next step: menu Edit -> Give Hint. It will be marked until you change the position in the puzzle.
Solve Step
The hint didn't help? Let SUDOKUMAT solve the next step for you, via menu Edit -> Solve Step. Take a moment to look at it and find out, how it could be set!
Validate input
Activating the validation mode via Edit -> Validate Puzzle lets SUDOKUMAT check every digit you enter. Even more, using the mouse-right-click-popup-menu, you will only have to choose between valid numbers (based on current puzzle state;-) for that cell.
Highlight relevant cells
Need some support when looking at the puzzle? Try turning on the tracker via View -> Show Tracker. This will highlight all cells that are relevant to apply the Sudoku-rules for the current cell.
Show possible positions
There are several possibilities to show all possible rule-conform positions of a digit: (all clicks are left-clicks)
1. Click on the button with the desired digit. Click on the empty button resets the marks.
2. Click on a Sudoku-field with the desired digit. Click on an empty Sudoku-field resets the marks.
3. Simultaneausly pressing the Alt-key and the desired digit. Simultaneausly pressing the Alt- and space-key resets the marks.
4. Pressing the Shift-key in a Sudoku-field with the desired digit. Pressing the Shift-key in an empty Sudoku-field resets the marks.
Grid- and font-size
Problems with your eyes? Enlarge the SUDOKUMAT-frame, that should help! The font is proportionally enlarged.
Clipboard usage
Sudokumat supports copy and paste for puzzles via the system clipboard. Format:
1. free cells as '.' and
2. values as digits
Automatic save of options
When you quit Sudokumat, the current options and the active puzzle are saved to a file, that is used at the next startup to initialize Sudokumat. The file is named Sudokumat.cfg and resides in the Sudokumat directory.

Create PDF-Files

One of the nice capabilites of SUDOKUKMAT is PDF-generation using the iText-library, version 2.0.4.

You want to do some paperwork? No problem - just generate lots of puzzles into a PDF-file and print it.

The Toolbar

The Toolbar provides buttons for the most important functions to improve the usability of Sudokumat.

Button	Description
New	Create a new puzzle with the currently selected level.
PDF	Create a PDF-file with many puzzles and - optional - solutions. The number of puzzles and their level are adjustable.
Undo	Undo the last change-activity
Redo	Redo the next change-activity
Copy Puzzle	Copies the puzzle (the fat values only, i.e. the problem) in a human readable format to the system clipboard. Example: `....2......3..41..9.8....37.17.3.4.......9....2.6.78...7...8...5......2....1...8.`
Paste Puzzle	Insert the content of the clipboard into Sudokumat. A currently active puzzle is overridden if you confirm this action.
Give Hint	Show an appropriate cell for determining the next digit.
Solve Step	Set one value by logic.
Enter Values	Activates the input mode for values.
Enter Candidates	Activates the input mode for candidates.
Show Candidates	Show all possible candidates for each empty cell.
Clear Candidates	Clear all candidates.
Clear mark	Resets all marks.
Mark positions	Marks all permitted positions for the chosen digit.

The Menu

The File Menu

Item	Description
New	Create a new puzzle with the currently selected level.
Clear	Create an empty puzzle. This is a good starting point to rip puzzles.
Save as Text	Save the current puzzle to a textfile.
Load from Text	Load a puzzle from a textfile, that was previously created by the "Save as Text" action.
Save as PDF	Create a PDF-file from the current puzzle.
Create Sudoku Book	Create a PDF-file with many puzzles and - optional - solutions. The number of puzzles and their level are adjustable.
Quit	Quit SUDOKUMAT.

The Edit Menu

Item	Description
Undo	Undo the last change-activity
Redo	Redo the next change-activity
Give Hint	Show an appropriate cell for determining the next digit.
Solve Step	Set one value by logic.
Solve Puzzle	Solve the current puzzle.
Fix Puzzle	Make all set values part the the problem. This is the way to rip puzzles!
Reset Puzzle	Reset to the original puzzle.

The Options Menu

This menu lets you set the input mode, some display options and the level of the Sudokus to be generated. A level is defined by the range of preset values, the number of simple possibilties on the way to the solution and the number of trial-digits (only in level Evil).

Item

description

Level

Random	Generate a puzzle with 0 - 44 values set.
Ultra-Easy	Generate a puzzle with 34 - 44 values set.
Easy	Generate a puzzle with 27 - 34 values set.
Medium	Generate a puzzle with 24 - 27 values set.
Hard	Generate a puzzle with 0 - 24 values set.
Evil	Generate a puzzle with 0 - 24 values set with at least one decision needed.

Enter Candidates

Switch between input mode for values and candidates.

Validate Puzzle

If enabled, SUDOKUMAT will check every value that you set against the rules. Attention: The result of the check depends on the current state of the puzzle, not the solution!

Show Tracker

If set, highlights the current row, collumn and area.

Show Candidates

Show all possible values for each empty cell.

Clear Candidates

Clear all candidates.

Colors

Set the color of the grid-background, selected grid-background and foreground via submenus and a Colorchooser-dialog.

Reset Size

Resize SUDOKUMAT to its start size.

Select Language

Choose the language to display menus, messages and help. Currently German and English are supported.

Save Options

Saves the current settings in the file Sudokumat.cfg in that directory, where Sudokumat is located (installed).

The Help Menu

Item	Description
Help	Show this help in an extra frame.
About	Show the about message. Click somewhere into the panel to close.