Sorry, puzzles older than one week are no longer available, setting the date to 24 Jul 2010
24 Jul 2010 | Day after | Today Show solution Print this puzzle Books
I read about KenKen® (also known as CalcuDoku) in the New York Times the other day, and decided to write a program that creates similar puzzles. The rules are: (1) the 4×4 puzzle uses the numbers 1-4, the 6×6 the numbers 1-6, and so on. (2) in each row and in each column each digit can appear only once (just like in Sudoku). (3) each "cage" (the blocks with the thick border) shows a result and an operation (addition: +, subtraction: -, multiplication: ×, or division: :). The operation applied to the numbers in the cage should produce the result shown. Note that for subtraction and division the order is not fixed (!) Look at the solutions of earlier days to make things clearer.
You can solve the puzzle on the page using the arrow and number keys. Use the spacebar to clear a cell. Use backspace to undo a move. In the largest puzzles (10x10 Calcudoku puzzle (every Friday) and 12x12 (every Sunday)), simply press 1 then 0, or 1 then 1, or 1 then 2 to enter 10, or 11, or 12. Tomorrow's puzzles will appear in hour(s) and minute(s). Every puzzle has a single solution.
