The New Sudoku Players' Forum

[richardm]

I made a meal of solving this one using only forcing nets. What's the more direct approach?

Code: Select all

..5 8.3 .9.
... ..1 ..4
9.. ... 6..

1.. ..4 .39
... ... ...
62. 1.. ..8

..4 ... ..6
8.. 7.. ...
.1. 9.2 5..


Richard M

[Carcul]

You have several naked pairs and triples. Look closely.

[bingham]

Hi,
I am new to this forum, so I know only a few of the names for techniques!
As Carcul pointed out, there are two naked pairs (k1/k9=3/7 and k5k8=4/8), one trio (b/g/h7=3/8/9), and one quartet (a/d/e/f7=1/2/4/7).
Once those are identified the only trick is finding the best fork to start your "trial and error" from. Either luck or instinct led me to h5/k5=4. k5=4 very soon leads to a contradiction, and h5=4 (k8=4,k5=8, etc.) starts a straight path, with no more forks, to the end.
Not fiendish at all!
JB

[wintder]

Hi,
I am new to this forum, so I know only a few of the names for techniques!
As Carcul pointed out, there are two naked pairs (k1/k9=3/7 and k5k8=4/8), one trio (b/g/h7=3/8/9), and one quartet (a/d/e/f7=1/2/4/7).
Once those are identified the only trick is finding the best fork to start your "trial and error" from. Either luck or instinct led me to h5/k5=4. k5=4 very soon leads to a contradiction, and h5=4 (k8=4,k5=8, etc.) starts a straight path, with no more forks, to the end.
Not fiendish at all!
JB

I look at the Carcul post, then yours.

Why?

[bingham]

Being equally brief: Why what?

[Cec]

".....I am new to this forum, so I know only a few of the names for techniques!....."

Hi bingham,
As you are new to the Forum you may not have yet become acquainted with the recommended procedure when posting. If you click on HERE you can read up on the preferred posting procedure and also click on this Basic Terminology link.

Note that cells are defined by their specific row and column rather than using alphabet letters. As the saying goes, the chorus sounds better when we use the same music sheet.

As Carcul pointed out there are several naked pairs, etc. though I also had to use the "Locked Candidates" technique to unfold the puzzle prior to naked singles popping up everywhere to solve it. No "trial and error" is required to solve this puzzle. There are many links describing solving techniques but I found the clearest explanation of "Locked Candidates" and other basic techniques was explained click here when I first joined the forum. Good luck with your homework

Cec

[bingham]

Thanks CEC for the guidance and encouragement. I have always been tempted to resort to T&E too soon. It works of course, but is not so elegant.
Actually, on this one I'm not sure which of all those techniques i used, but i got there anyway!
Bingham