How to solve this puzzle

Gowin · Posted: Mon Oct 24, 2005 2:31 pm Post subject: How to solve this puzzle

I am new to sudoku and trying to make a sudoku-solver...

The program can handle the easy ones but now i want to try on
the harder ones... like this:

(red is the original puzzle, and blue numbers are added by my program)

My program can detect naked and hidden singles.. using xy-wing
not entirly sure on the names...

What do i need to add to make this solvable for my program
not really sure how to solve it without guessing

thanks

kranser · Posted: Mon Oct 24, 2005 3:59 pm Post subject:

You need to implement hidden singles on boxes (blocks).

I.e. if a Box has candidates for a value that occur only within one particular row, then you can exclude that value from the rest of the row (except the part of the row that is in the box).

See Block and Column / Row Interactions here: http://www.simes.clara.co.uk/programs/sudokutechniques.htm

Kranser.
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Gowin · Posted: Mon Oct 24, 2005 4:27 pm Post subject:

Thank you for answer...

edit: i can see that i solves the puzzle.. thank you

Now i only need to try and implement it :S

weia · Posted: Sat Nov 12, 2005 8:04 pm Post subject:

Your programm found one hidden single less than mine. (6th column, 8th row).