Forcing Chain Problem

Post the puzzle or solving technique that's causing you trouble and someone will help

Postby daj95376 » Tue Apr 29, 2008 10:30 pm

ronk wrote:
daj95376 wrote:if my broken segments can only be expressed as an ALS-something, then I'll find a workaround.

As for my chain module, I'm still in development Phase I where I'm only working with Naked/Hidden Singles.

ALSs appearing simply means the singles are due to multiple inferences instead of a single inference ... as for the following:
daj95376 wrote:3r1c4 4r4c4 7r5c6 [b2]~8
3r2c4 4r4c4 7r5c6 [b2]~8
3r3c4 4r4c4 7r5c6 [b2]~8

I'm not sure if we're thinking the same thing for this last example. Since my new solver doesn't handle grouped chains right now, I was indicating that three individual chains were currently found instead of the following grouped NL chain.

Code: Select all
[r123c4]-3-[r4c4]-4-[r5c6]-7-[r3c6]-8-[r2c5]~3~[r123c4]; => [r123c4]<>3

[Edit: Here is the NL chain that I couldn't get right earlier. Unfortunately, it doesn't lead anywhere. I made the mistake of applying the elimination to the wrong cell when looking to see if it cracked the PM.]

Code: Select all
[r2c7]-6-[r78c7]-45-[r6c7]=4=[r6c9]=6=[r6c4]-6-[r3c4]~6~[r3c79]; => [r2c7]<>6

Definitely not my day:!:
Last edited by daj95376 on Wed Apr 30, 2008 1:00 am, edited 1 time in total.
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Postby ronk » Wed Apr 30, 2008 1:53 am

daj95376 wrote:
Code: Select all
[r123c4]-3-[r4c4]-4-[r5c6]-7-[r3c6]-8-[r2c5]~3~[r123c4]; => [r123c4]<>3

OK, apparently you used an SSTS first. I took your post literally ... and had r3c6=378 for ...

r123c4 -3- r4c4 -4- r5c6 -7- als:[r3c6,r2c5] -3- r123c4 => r123c4<>3
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