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Sudoku Xtra magazine, written by Gareth Moore
Sudoku Xtra 8
magazine

Sudoku
 
Hanjie
 
Kakuro
 
Futoshiki
 
Hitori
 
Killer Sudoku
 
Slitherlink
 

Sudoku-X
 
Jigsaw Sudoku
 
Toroidal Sudoku
 
Killer Sudoku-X
 
Jigsaw Killer
 

Sudoku 6x6
and variants
 
Sudoku 12x12
and variants
 

Looking for puzzles for your book, magazine or newspaper?
 

 
 

Hitori Puzzles by Dr Gareth Moore

Example Hitori puzzle
Hitori

In a Hitori puzzle you start with a full grid and must eliminate numbers by shading them in so that no number occurs more than once in any row or column - conceptually it's a little bit like Sudoku in reverse, but in practice the logic require dto solve the puzzle has very little in common. In particular there is no requirement to have each number occur at least once in a row or column (which would not be possible in a Hitori puzzle with a unique solution in any case).

The rules of Hitori are:

  • Some squares must be shaded so that no unshaded number is repeated in a row or column
  • No shaded square can touch any other shaded square horizontally or vertically (they may touch diagonally however)
  • You must be able to 'travel' from any unshaded square to any other unshaded square simply by moving left/right/up/down from unshaded square to unshaded square

There is only ever one possible solution to any Hitori puzzle, which can always be reached via reasonable logical deduction. In a proper puzzle every square must be forced to be either shaded or unshaded (white or black) - in some inferior copies of the puzzle this requirement is not obeyed, so beware of pale imitations! Guessing is never required.

Because many arrangements of numbers form technically-valid Hitori puzzles, you may have come across poor Hitori 'puzzles' that actually require no thought to solve (or conversely are ridiculously tricky). None of my puzzles are like this - I seed puzzles by hand with interesting layouts that ensure interesting (but not insanely-tough) logic is needed to reach the solution.

I can supply Hitori puzzles at a range of sizes and difficulties.


Choose from one of the following options:

  • Play an interactive Hitori puzzle online now
  • Play a wide range of free puzzles online
  • Obtain Hitori puzzles for your publication


    Some more puzzle types from Dr Gareth Moore - click on a puzzle to view further varieties:
  •  
    Play Hitori Online Now!
    More Hitori samples:
    (click to enlarge)
    Please note: all puzzles supplied for publication are in rescalable vector-format PDF format unless otherwise requested.

     

    All site contents ©Gareth Moore 2005-2010 - email gareth@puzzlemix.com - information about my published books, magazines and more