Hyper Sudoku Online Help

Rules

Hyper Sudoku follows the same rules as Sudoku in that every row, column and block of the grid must contain the numbers "1" to "9". But it has an additional four shaded blocks (referred to here as "hyperblocks"), each of which must also contain the numbers "1" to "9".

How To Play

  • Move your cursor over the "New Puzzle" menu item and select a skill level from the dropdown menu.
  • Fill in blanks with the Pen (select a cell, then click on the number you want to enter, or enter the number via the keyboard).
  • If you are not 100% sure of a number, you can make a note of it in the cell using the Pencil. To do this, click the "Pencil" icon to be placed in "Pencil mode".
  • You may enter as many pencil marks as you like in each cell.
  • To change back to "Pen" mode, click the "Pen" icon. You can also switch between pen and pencil modes quickly by pressing the "P" key. (See tips below.)

Input Tips

Keyboard
If you prefer to use the keyboard rather than the mouse, you may:
  • Use the arrow keys to navigate around the grid.
  • Use the number keys to enter a number in the highlighted cell.
  • Press the space or Delete key to remove any numbers from the highlighted cell.
  • Press the "P" key to toggle between Pen and Pencil.
  • Press the "U" key to undo last input.
  • Hold Shift key down to enter in pencil (when in Pen mode).
Other Tips
  • Click the Undo icon (yellow arrow) to undo last input. You can undo all the way back to the beginning.
  • Holding the Shift key when clicking on a number in the input panel will pencil that number in. You may find this more convenient than toggling between the Pen and Pencil icons.
  • To remove just one pencilled number in a cell, enter that number again.
  • To remove all pencil numbers in a cell, either click the eraser button or simply "pen" the final choice in.
  • To remove all pencil nubers from all cells, use the menu option under "Edit".
  • There is an alternate mode of number input via the mouse called "Active Number Mode" (see below).
Active Number Mode
If you select this mode (via Edit->Preferences menu option), then the number you click from the Number Pad on the right becomes the "active number". The mouse cursor will change to this number and clicking on any cell will enter it in that cell. This is the reverse of the "cell select" mode, where you highlight a cell and then select the number to input. Those that prefer to solve by focusing on one specific number at a time will find this mode much more convenient.

To change the active number, select a new one from the Number Pad or scroll the mouse wheel down/up to increase/decrease the number.

In the Active Number mode, all pencil functionality remains the same as does the ability to use the keyboard.

Description Of Menu Options

New Puzzle Menu

Here you can generate a puzzle at the required level of difficulty. All these puzzles are solvable by pure logic.

Note: Initially, there is only one new puzzle per level per day.

Edit Menu

Undo
This will undo the last move. You can undo all the way back to the beginning of the puzzle (unless you have loaded a puzzle which was partially completed). This is the same as clicking the Undo icon (yellow arrow).
Clear Possibles
This will clear all possibles displayed in the grid.
Clear All Input
This will clear all input (pen and pencil marks).
Pencil Marks to Pen
This option will convert all cells that have one pencil mark to a pen mark. The "C" key is a shortcut key for this option.
Save
Saves the current state of the puzzle to temporary user data on this computer. This is useful if you wish to come back another time to continue solving it, or if you are guessing which may necessitate you to backtrack later on.
Load
Loads the last saved puzzle on this computer.
Print
Prints the current state of the puzzle.
Preferences
Here you may set whether you wish automatic display of errors, whether you want sound effects or not or whether you want to enable "Active Number" mode. Auto error display means that as you enter a number in a cell, it will display in red if incorrect. You can also change input and other colors.

Preferences are remembered and will reload from what was last set on that computer.

Solve Menu

Main options to aid in solving puzzles.
Check Input
Checks to see if you have solved the puzzle correctly. Any errors made will be shown in red.
Hint
Suggests which cell may be the next easiest to solve. It will not fill in the value - for that you need to select the "Solve One Cell" option.
Clue
This will suggest you look where a particular number is located in a block, row, column or hyperblock and will highlight that area of the grid. This helps you more than the "Hint" option and is the easiest aid you can ask for, save getting the actual answer.
Solve One Cell
This option will fill in one of the cells and displays the reason why that number is the answer to the cell.
Possibles Level 1
This option will show you the obvious possible numbers for each unsolved cell. It does this by looking at what numbers are already present in the same block, row, column and hyperblock.
Possibles Level 2
This option uses more sophisticated logic strategies in determining possible numbers for each unsolved cell. It looks at each possible number in each cell and sees if this number can be placed anywhere else on the same row/column/block/hyperblock. If not, the possibles for that cell are reduced to just this number (ie it is the solution for that cell). It also uses the "Rule of k" (for lack of better label).

Rule of k

The "Rule of 1" means that if a cell has only one possible value, then all other cells in the same region (row/col/block/hyperblock) cannot have that value (uniqueness of digits).
The "Rule of k" is just an extension of this rule which says that if there are k cells in a region that each contain exactly the same k different possible values, then no other cell in that region can contain any of those k values. Therefore we can eliminate those possibles from the other cells in the region.
For example, if two cells in a row both contain the possibles "34" only, then we know that one of the cells is a "3" and the other "4" (although we don't know which is which). But it does mean that no other cells in the same row can be a "3" or "4" so we can eliminate those numbers as possibles for them. The same logic can be applied to 3 cells with the same 3 possible values, and so on.

Solve
Solve the puzzle and shows the completed solution.