The New Sudoku Players' Forum

[jandenny]

I am stuck please tell me the next step and the logic behind it.
Thanks
Jan

Code: Select all

 5 3 4 | 9 . . | 2 8 .
 . . 7 | . 5 . | . 3 .
 . . 8 | . . . | 7 . 5
-------+-------+------
 4 6 2 | 7 3 9 | 1 5 8
 9 7 1 | 4 8 5 | 3 . .
 8 5 3 | 1 2 6 | 4 7 9
-------+-------+------
 7 4 6 | . . . | . . .
 2 8 9 | . 7 . | . . .
 3 1 5 | 6 . 2 | 8 . 7



[Pat]

hi jandenny

you probably need a "forcing chain"

e.g.

if r2c2 = 9 then r7c7 = 9, r7c4 = 5, r2c4 = 8, r2c2 = 2

-- the contradiction proves that r2c2 not 9