What to do when all slots have more than one possibility?

Advanced methods and approaches for solving Sudoku puzzles

What to do when all slots have more than one possibility?

Postby Cram » Fri Aug 26, 2005 7:42 pm

Im new to Sudoku and found this puzzle where every open slot has at least two possibilities, what would be the next step?

Thanks a bunch.

Code: Select all
 
_ _ _   4 6 _   1 _ _
_ _ 2   1 _ _   7 8 _
1 _ _   8 _ 2   _ _ 4

5 7 1   6 _ _   4 _ _
_ _ _   2 4 1   _ _ _
_ _ 4   _ _ 5   _ 3 1

8 1 7   3 2 6   5 4 9
_ 5 6   _ _ 4   2 1 _
_ _ _   5 1 _   _ _ _

Cram
 
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Joined: 25 August 2005

Postby PaulIQ164 » Fri Aug 26, 2005 7:53 pm

As well as checking which numbers can be in the cells, it's important to check which cells in a particular row/column/box can hold each number. So, in your example, if you look at the third row down, there's only one cell that the 7 can be in (the middle one).
PaulIQ164
 
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Joined: 16 July 2005

Postby kf-ryan » Sat Aug 27, 2005 12:16 am

Check out the solving techniques at
http://www.paulspages.co.uk/sudoku/howtosolve/

It is an extremely helpful sudoku site. Pay attention to 1. crosshatching, 2. slicing & dicing, and 3 pencilling in. When you move on to more difficult puzzles pay attention to the rules about pairs, triplets, and such

Ken
kf-ryan
 
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