Su Doku
by submission
Image text: This one is from the Red Belt collection, of 'medium' difficulty
This comic provided by Rik 't Hoff. http://www.facebook.com/profile.php?id=516678350
First off, a little background: Su Doku (Japanese for single number) is a kind of puzzle, in which the player must place numbers (usually 1-9) in a (9 by 9) matrix playfield in such a way that no number appears twice on a horizontal and vertical row, and in a region of nine numbers in said matrix. Depending on the number of pre-filled numbers, the difficulty increases as the possibilities widen. The image text refers to the “Red Belt”-collection, which is a series of extreme difficult puzzles.
Now to the joke: when you play binary Su Doku, you only end up with two numbers (0 and 1), thus creating a maximum playfield of 2x2. Even the “Red Belt” series therefore will be easy to solve, as you can see in the comic.
January 6th, 2012
Incidentally, traditional non-binary su doku’s have now been solved – http://www.newscientist.com/blogs/shortsharpscience/2012/01/sudoku-mystery-solved.html
January 6th, 2012
In fact, Randall is wrong here, the base of a sudoku must be a square number.
January 9th, 2012
To be technical, you are correct; because if you fill this in with a 0 on top and 1 on bottom, you actually have a single 4-square block with two 0s and two 1s (remember you can’t have the same digit anywhere inside a square block). But I don’t think he was being this technical when he created the comic. Technically this 4-square puzzle would require 4 digits to complete, and a 2-digit (binary) puzzle would not work.
January 10th, 2012
I don’t think Randall is wrong, in fact, that is part of the joke.
This puzzle is impossible to solve (because of the base) yet it is still only of medium difficulty in the Red Belt collection.
January 7th, 2012
Try to solve it. It is impossible.
(Try to push a one into the bottom left, and you are left with two same numbers in the diagonal.)
January 7th, 2012
diagonal matches are allowed – it’s rows, columns and blocks that aren’t
January 9th, 2012
A few notes from my own explanation of this one:
I believe the image text references a series of published Sudoku puzzle books called the “Martial Arts Sudoku” series. The difficulty of each book denoted by a belt colour which itself references the fact that in many Martial Arts, participants are awarded coloured belts when they reach certain skill levels, with each colour representing a certain skill level. In the series, red belt was level 8 (of 9) just below black belt. So the joke is that there is no way to make binary Sudoku difficult, and so this is a “medium” difficulty puzzle within the second-highest level of binary Sudoku books.
Finally, there may also be an in-joke in the comic title “Su Doku” – the space after the ‘Su’ may be a superuser (linux) reference; although putting the space before the ‘ku’ would have given ‘Sudo’, which is another linux command. It’s possible Randall simply thought there was a space in the word Sudoku; but Randall usually researches pretty well.
February 2nd, 2012
anyone thought of the linux-command: SU (substitude user)?
further: I thought in a sudoku-matrix the numbers can only appear once! Thus, the puzzle is insolvable afterall..
best
February 2nd, 2012
aww I should read the other posts before writing an own one.. i guess
never mind though
February 15th, 2012
Also, sudoku puzzles do NOT have to be square numbers. 6 works quite well.