6:50 PM — Sudoku This summer at CTY a number of my fellow instructional staff (sammka) were absorbed by this thing known as Sudoku. I'd heard of it before, and I didn't quite get why it was so fascinating, especially since I barely got 6 hours of sleep as it was without adding additional distractions. A few weeks later in London I finally saw one in The Guardian and gave it a stab. It was a hard one, and I only got two rows in the end, but it was really fascinating. For the 8 hour plane ride back, I bought a couple books of it for me and T$ to keep trying. FINALLY just yesterday I found a link to WebSudoku.com, and it's probably going to supplant PBN as my internet time-waster when I've used up all the webcomics.

What is Sudoku? It's a logic puzzle that originally came from Japan (supposedly). The numbers 1-9 are used, but they're really just symbols, you don't do any math with them. You're handed a 9 by 9 grid, broken into nine smaller 3x3 boxes. Some of the numbers are already filled in, and you have to fill in the rest. There are only three rules.

• Each number 1 through 9 appears in each row once (and only once).


• Ditto each column.


• Ditto each 3x3 box.

It's amazing how fiendishly difficult they can get with just those three rules. Now go and try it!  ¶ permalink | 1 musings