Dave Child's Workshop

Colour Sudoku

I've launched a fun side project - Colour Sudoku (ed: now closed), a new type of sudoku puzzle where you have to place the numbers 1-9 in every row, column and blocks of a single colour (so 1-9 in the yellow boxes, 1-9 in the blue boxes, etc). Here's an example:

          4 3   5
        4   9    
    2 5          
      6       9 7
            6    
2               4
5 9 3 1   2      
                 
  6   7       1  

For a while, the code for this generated a new puzzle every day on coloursudoku.com, but eventually I mothballed the site. If you'd like more of these, please let me know and I'll see what I can do about adding the generator here.