Code-Doku puzzles blend the logical challenge of normal sudoku puzzles with a surprise message that is revealed as you work toward a solution. Instead of using the digits one through nine, Code-Doku puzzles use letters. Other letter-based puzzles such as Go Doku (or Godoku), Sudoku Word or Wordoku have a hidden word, often down the diagonal. Code-Doku puzzles have shaded squares that contain the hidden message. When you have determined the solution to the puzzle, the letters in the shaded squares will spell out the hidden message.
Cube Sudoku puzzles are formed on the six faces of a cube. Each face has a 4×4 grid. The sixteen values must be placed so that each value appears exactly once on each face. In addition, the rows and columns on each face extend all the way around the cube. Each of the sixteen values must also be placed so that each value appears exactly once in each of the twelve strips.
The Sudoku of the Day page features sudoku puzzles in a variety of novel configurations. Like Cube Sudoku, the rows and columns of these puzzles may curve, so that the same strip may pass through one box as a row, but pass through another box as a column.
If you'd like to be notified when new puzzles are posted, just send me an e-mail at the address below. For more information about these puzzles, please check out the Code-Doku and Cube Sudoku pages. Good Luck!
Current Code-Doku Puzzle
This puzzle was suggested by Arnie Miller in San Mateo, California.
A Special Treat
by Steve Schaefer
Place each of the letters of BE SPINACH exactly once in each row, column and 3×3 box. When you have completed the puzzle, the shaded squares can be read left to right, then top to bottom to form a phrase describing a special treat.
Anagram: BE SPINACH
The image below is the current "Easy" Cube Sudoku puzzle. You can get a larger version of this puzzle, the solution, and more difficult puzzles at the main Cube Sudoku page.
Other Sudoku Puzzles and Links
Sudoku of the Day -- Daily puzzles, mostly with 3x3 boxes connected by curving row/columns.
Code-Doku -- The main page for code-doku puzzles (with previous puzzles).
Cube Sudoku -- The main page for cube sudoku puzzles.
Code-Doku Archive -- Previous code-doku puzzles from this site.
Code-Doku FAQ -- More information about Code-Doku puzzles and how to solve them.
Top Notch -- The only other source for Code-Doku puzzles.
Top 50 Sudoku Sites -- A collection of links to sudoku puzzles, solvers, games and more.
Beginner's Introduction to Sudoku -- This is all you need for the easy and moderate puzzles when I give a full set of difficulty levels for a codedoku.
Sudoku Solving Techniques -- This site presents more advanced techniques for solving tricky, fiendish and extreme puzzles.
Sudoku Methods -- My own description of sudoku methods. It's not as polished, but it includes some methods that do not apply to the classic 3×3 grid of 3×3 boxes.
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