@ 2012-03-16 9:11 PM (#6940 - in reply to #6939) (#6940) Top
Posts: 337
Country : Switzerland
Fred76 posted @ 2012-03-16 9:11 PM
Finally (then I stop and let you concentrate on the tapa contest 
), I want to speak about the diagonal twin sudoku.
There is (at least) 2 openings for these grids. You can begin with the corners. With grid A you can place 8 in R1C9, 4 in R9C9, and Grid B let you know the two other corners.
But there is another opening, which I find more elegant: You can start with the center of the grids: box 5. Grid A let you know that digits in white cells are 3,5,7 and 8. Knowing that individually they can't be placed in the same cell let you place the 5 in R5C6, the 3 in R5C4, then the 8 in R6C5 and 7 in R4C5 in grid B.
Then in both grids, 6 can be placed in R5C5, you have a pair 14 in cells R6C46, then 2 in R4C4 and 9 in R4C6.
Of course, you'll need still lot of work to solve these grids, but box 5 is almost filled
(diagotwin2.png)
Attachments
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diagotwin2.png (18KB - 0 downloads)
), I want to speak about the diagonal twin sudoku. There is (at least) 2 openings for these grids. You can begin with the corners. With grid A you can place 8 in R1C9, 4 in R9C9, and Grid B let you know the two other corners.
But there is another opening, which I find more elegant: You can start with the center of the grids: box 5. Grid A let you know that digits in white cells are 3,5,7 and 8. Knowing that individually they can't be placed in the same cell let you place the 5 in R5C6, the 3 in R5C4, then the 8 in R6C5 and 7 in R4C5 in grid B.
Then in both grids, 6 can be placed in R5C5, you have a pair 14 in cells R6C46, then 2 in R4C4 and 9 in R4C6.
Of course, you'll need still lot of work to solve these grids, but box 5 is almost filled
(diagotwin2.png)
Attachments
----------------
diagotwin2.png (18KB - 0 downloads)