Slashdot Mirror
The Godfather of Sudoku
circletimessquare writes "The New York Times profiles 55 year old Maki Kaji who runs Nikoli, in its article Inside Japan's Puzzle Palace. Nikoli is a puzzle publisher that prides itself on 'a kind of democratization of puzzle invention. The company itself does not actually create many new puzzles — an American invented an earlier version of sudoku, for example. Instead, Nikoli provides a forum for testing and perfecting them.' Also notable is how Mr. Kaji describes how he did not get the trademark for Sudoku in the United States before it was too late. But reminiscent of a theme many Slashdotters will find familiar about intellectual property: 'In hindsight, though, he now thinks that oversight was a brilliant mistake. The fact that no one controlled sudoku's intellectual property rights let the game's popularity grow unfettered, Mr. Kaji says.' Will Nikoli be the source of the next big puzzle fad after Sudoku?"
Nikolai makes my favorite type of puzzles, Nurikabe. Hopefully those will pick up in the US too.
What is ku, and why is he running it as root?
If the masses can keep you down, you're not the Ubermensch.
Actually a generator which will generate puzzles at a given level of difficulty is not too hard if you organize the solver as a rule based system (Rule 1: first look to see if there is a square that only allows one number; Rule 2: look for pair of numbers that must exist in a pair of cells{sometimes called hidden pairs} . . . )
After you create the rules that will solve the puzzles you categorize the rules as easy, medium or hard.
Now if you want to create an easy puzzle you start randomly adding in (legal) numbers and each time you try to solve it using only the easy rules. The first time the solving part of the program solves the puzzle you are done. Alternatively you can start with a completed puzzle and remove a number and see if the number you removed is recoverable with the level of rules (easy, medium, hard) that you choose for the final puzzle.