Sudoku - a simple yet challenging puzzle
Sudoku rules: Complete the grid so that every row, column, and 3-by-3 box
contains every digit, 1 to 9.
The puzzle shown above is an easy one -- give it a try. The solution is shown at the end of this page, but try
solving it on your own before looking. Hint: In the
top row, a 1 may be placed in the 7th square only. It can't
go in the 1st, 2nd, or 6th squares since those 3-by-3 boxes
already have a 1.
The contest: Typeset this grid
using TeX macros. You may use LaTeX, ConTeXt, plain TeX,
AMSTeX, or your favorite set of macros.
For some ideas on how to compose the basic grid, see Will Robertson's
Square cells
paper. There is also a Sudoku package on CTAN, but for this
contest you must write original macros.
Beginners category. Typeset the grid as shown above.
This category is open to those who have been using TeX for less than one year.
Regular category. Create a new macro,
\sudoku{file}, which
reads a sudoku puzzle file and then typesets the grid. A
sudoku puzzle file is a simple text file with nine lines, and
each line has nine characters: the digits 1-9 or (.) for a
blank square.
For Wizards only. Create a new macro,
\sudokusolve{file},
which which reads an easy sudoku puzzle file, solves it, and then typesets
the solved grid. See this Sudoku web site for
some sample automated solving methods.
How to enter the contest: Send
your source file and either a pdf or dvi file to
Sudoku. Put your name in the subject line of the
email. Entries must be received by January 15, 2006. After
the closing date we will select submissions at
random and the first three in each category with correct answers will receive
a souvenir PracTeX postcard.
More about Sudoku. A good site to start with is Sudoku Solver.
It has a free automated solver that will show you step-by-step how
it's done. There are numerous other
sites that offer free and
shareware Sudoku solvers and sample puzzles. Warning:
these puzzles can be addictive.
Winners of the previous Distractions contests
Winners of the Pitfalls Contest:
Gianluca Pignalberi
Ed Thoele
Mads Sorensen
Reinaldo Pis Diez
Brian Elmegaard
Winners of the Web Treasure Hunt:
Barbara Beeton
Joy Morris
Javier Mateos
Klaus Hoeppner
Answers.