## Nice loops for elementary level players - the x-cycle

Advanced methods and approaches for solving Sudoku puzzles
aeb wrote:(1,6)2 is ruled out as follows:
If (1,6)2 then (456,6)468 and (789,5)2478, but four digits cannot be in three cells.

But if (1,6)2 then (123,5)368 and (789,5)247 ... so I have doubts that your elimination is valid.

(123,5)2368 and (789,5)2478 are doubly-weakly-linked ALSs and share the 2 and the 8. We just don't know which set will hold which. But we do know neither set must hold both ... no matter what happens at (1,6).

Ron
ronk
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ronk wrote:
aeb wrote:(1,6)2 is ruled out as follows:
If (1,6)2 then (456,6)468 and (789,5)2478, but four digits cannot be in three cells.

But if (1,6)2 then (123,5)368 and (789,5)247 ... so I have doubts that your elimination is valid.

Shame on you. Think about (456,6)468 and where the 8 goes in box 8.
aeb

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aeb wrote:Shame on you. Think about (456,6)468 and where the 8 goes in box 8.

I stand 1/2 corrected. Think about it, you've got the correct result, but the wrong reason.

Ron
ronk
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ronk wrote:
aeb wrote:Shame on you. Think about (456,6)468 and where the 8 goes in box 8.

I stand 1/2 corrected. Think about it, you've got the correct result, but the wrong reason.
Ron

More shame on you. At least you understand now. Exercise: write this as a nice loop.
aeb

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aeb wrote:More shame on you. At least you understand now. Exercise: write this as a nice loop.

After tacky comments like that, I'll be sure not to post to you again. Please return the courtesy.

Ron
ronk
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### Nice loops for elementary level players - the x-cycle

Jeff wrote:BTW, this is no ordinary grid. You might like to solve it from the beginning:
Code: Select all
` *-----------* |1.8|4..|5..| |...|..7|..2| |...|...|...| |---+---+---| |.2.|.9.|..7| |.6.|.5.|.89| |9..|.1.|.4.| |---+---+---| |...|...|...| |5..|6..|...| |..4|..3|9.8| *-----------*`

I am curious, my counts are 10 simple nice loops, 7 ALS and 1 unique rectangle. Do you find anything more exotic? By itself, I admit that this is definitely not ordinary.
Thanks, flip
flip

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Joined: 08 January 2006

### Re: Nice loops for elementary level players - the x-cycle

flip wrote:I am curious, my counts are 10 simple nice loops, 7 ALS and 1 unique rectangle. Do you find anything more exotic? By itself, I admit that this is definitely not ordinary.

Hi Flip, I am quite surprised you were able to find so many simple nice loops in this grid; perhaps after a few ALSs. I haven't completely solved this one yet. Would you like to open a new thread and post your full solution for us?

Thanks in anticipation.
Jeff

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Joined: 01 August 2005

aeb wrote:My solution is not terribly complicated. The most interesting step occurs at this point:

What does "not terribly complicated" mean for you ? The elimination of 8 in r7c4 and 2 in r1c6 (the explantion was a riddle) were not the hardest part for me. Is the rest of your solution also that easy?
ravel

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ravel wrote:The elimination of 8 in r7c4 and 2 in r1c6 (the explantion was a riddle) were not the hardest part for me. Is the rest of your solution also that easy?

Yes, but I threw away the piece of paper. If there is a stage where you do not know what to do next I can probably give a possible next step. There were maybe a dozen steps, none very difficult.
aeb

Posts: 83
Joined: 29 January 2006

### Re: Nice loops for elementary level players - the x-cycle

Jeff wrote:I am quite surprised you were able to find so many simple nice loops in this grid; perhaps after a few ALSs. I haven't completely solved this one yet. Would you like to open a new thread and post your full solution for us?

Done, try here http://forum.enjoysudoku.com/viewtopic.php?t=3417
flip
flip

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