Sumocue hints

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Nick
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Sumocue hints

Post by Nick »

Please explain "Elimination in inner-outie differences in Box..."
I don't understand/can't work this out. I'm doing the latest Assassin Killer and looking at Box 2
Thanks
Ruud
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Post by Ruud »

Hi Nick,

here (I think) is the situation where you will first encounter an innie-outie difference in nonet 2:

Image

The 2 green cells are the outies.
The red cell is the innie.

The sum of the 3 cages covering nonet 2 is 43, so the 2 green cells together must be 2 less than the single innie.

The minimum value for the 2 outies is 3 (1+2), so the innie must be at least 5. You can eliminate digits 1 through 4 in the innie.

The maximum value for the innie is 9, so the 2 outies together can be a maximum of 7. This means that neither of them can be higher than 6. You can eliminate candidates 7 through 9 from these 2 cells.

Hope this helps you understand the technique.

Ruud
“If the human brain were so simple that we could understand it, we would be so simple that we couldn't.” - Emerson M Pugh
Nick
New kid on the Grid
New kid on the Grid
Posts: 3
Joined: Tue Nov 14, 2006 6:10 pm

Sumocue hints

Post by Nick »

Ruud - thanks for reply to my question on innie-outie differences on the latest Assassin Killer
I'm still trying to get my head round this and seem to have a mental blockage! Could you run through Nonet 3 and Nonet 7 innie-outie difference for me as well? With a couple more examples it may well click for me - I seem to react intuitivelyto these kind of problems if I have more examples
Many thanks
Nick
emm
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Post by emm »

Hi Nick

Here’s how I look at it.

Total for N3 = 45 = 27 + 18 - outies + innies.

=> 45 = 45 - r4c8 + r13c7 (in this case the 1 outie = the 2 innies)

From this you can make eliminations :
The min possible for any two cells (the innies) is 3 => the min for the outie also = 3

=> r4c8 <> 1 or 2 and you can eliminate them as candidates

Conversely, the max possible for any one cell (the outie) is 9 so you know that the max possible for the 2 innies is also 9.

-------------------------------------------------------------------------------------

Total for N7 = 45 = 22 + 24 - r6c1 (outie) + r7c23 (innies)

=> 45 = 46 - r6c1 + r7c23

=> r6c1 = 1 + r7c23 ( in this case the outie = the 2 innies +1)

The max for the outie = 9 => max for the innies = 8

=> r7c23 <> 8 or 9 and you can eliminate them as candidates

The min for the innies = 3 => min for the outie = 4

=> r6c1 <> 1 or 2 or 3 and you can eliminate them as candidates
Nick
New kid on the Grid
New kid on the Grid
Posts: 3
Joined: Tue Nov 14, 2006 6:10 pm

Sumocue hints

Post by Nick »

Ruud
Many thanks for your help - I think I am beginning to get the hang of it now. I love killers, having polished off the Times Killer Sudoku book, and finishing the Sudokulist Extreme Killer each week in fairly quick time. Strange how one gets a mental blockage sometimes!
Nick
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