## Question of logic

Programs which generate, solve, and analyze Sudoku puzzles

### Question of logic

I thought that all squares could be logically determined singularly. It now appears as if, in some cases, one must take one of shall we say two pencilmarks, and work it through to see if puzzle unravels. Is this correct?
rceggl

Posts: 1
Joined: 15 January 2006

Hi - you've only just joined the forum and so you probably don't realise you've stepped into a minefield. Actually - you've got both feet in two separate minefields!

Before the first one goes up think about this - What do you mean by logical? Do you think it's not logical to choose to try one and then the other of the only two possible candidates for a cell?

As far as the second one goes - I bet there are puzzles out there that you cannot solve except by choosing a candidate and trying it to see if it works. For myself, there are these puzzles also, but there are fewer now that I've learnt some techniques. I cannot speak for the others but quite a lot of them are very brainy and so there might be one or two who never have to do this.

PS : This has been posted in the wrong place in this forum - read this .
emm

Posts: 987
Joined: 02 July 2005

### Re: Question of logic

rceggl wrote:I thought that all squares could be logically determined singularly.

This is true. Though a child may be unable to reach the cookie jar on the high shelf -- this does not make the cookie jar unreachable. A cookie jar on the top of a Everest maybe out of reach for you, me and anyone we've ever met -- but it still isn't unreachable.
tso

Posts: 798
Joined: 22 June 2005