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 Post subject: GE NC FO DGT 3
PostPosted: Wed Feb 05, 2014 8:28 am 
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Grand Master
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Joined: Wed Apr 30, 2008 9:45 pm
Posts: 694
Location: Saudi Arabia
Greater than or equal to, Non-consecutive, Fully ordered, Digitised Killer 3

With the lack of DJApe killers I've gone back to KSO - which brought me to this one.

All cages are non-consecutive.

All cages are fully ordered e.g. 13579, row then column.

Equality/inequality is between cage totals.

Grey cages are digitised i.e. one of the cell values is the last digit of the cage sum. White ones are not digitised but I did not use this in my solution.

I seem to remember Para doing digital killers a couple of years ago - but I cannot remember what he called them.

Probably medium for Andrew - others may find it harder.


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 Post subject: Re: GE NC FO DGT 3
PostPosted: Wed Feb 12, 2014 7:08 pm 
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Grand Master
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Joined: Tue Jun 16, 2009 9:31 pm
Posts: 282
Location: California, out of London
Thanks HATMAN for another fine puzzle. Once I got my head wrapped round it and wrote out the possibilities for the digitized cages, it wasn't too hard.


Hidden Text:
All cages are 3-cell cages.
I use the phrase "?@rxcy" to mean "The unknown total cage at row x column y

The 3-cell 'digitized' cages must have two cells which total +10.
-> for those cages - the possible sequences and totals are:

[1(3-7)9] = +13 to +17
[2(456)8] = +14, +15, +16
[137] = +11
[357] = +15
[379] = +19
[(12)46] = +11, +12
[46(89)] = +18, +19

1. Min total ?@r1c1 = +11
-> Min total ?@r3c3 = +13
But 13/3@r3c3 would put a 1 in r3c3 and also in r1c1 (to give ?@r1c1 = +11)
-> Min total ?@r3c3 = +14

2. -> Min total ?@r7c7 = +18
Max total ?@r7c7 = +21 ([579])
Since r789c8 = r789c9 -> r789c7 = Odd total
-> ?@r7c7 is +19 or +21 and ?@r7c8 and ?@r7c9 are +13 or +12 respectively

But ?@r7c8 = +13 would require it to be [139] which leaves no solution for ?@r7c7 = +19
-> ?@r7c7 = +21 = [579]
-> ?@r7c8 = +12 = [246]
-> ?@r7c9 = +12 = [138]

3. In n5 HP (89) can only be in r5c6 and r6c4
-> Since ?@r4c4 is Min +15 and max +17 -> the 8 or 9 at r6c4 must be part of the two cells that add up to +10 in that cage
-> r46c4 = [19] or [28]

Similarly since ?@r4c5 = Max +16 -> r4c5,r5c6 = [19] or [28]
-> {12} in n5 in r4c45
-> HP (12) in n6 -> r56c7 = {12}

4. ?@r5c5 is Min +16 and Max +18 and does not have a 1 or a 2 in it.
-> Only possibility is ?@r5c5 = +18 = [468]
-> ?@r6c6 = +19 can only be [379]
-> HS 7 in n5 only at r5c4 -> ?@r4c4 = +17 = [179]
-> ?@r4c5 = [258]

5. HP (79) in c5 -> r23c5 = [79]
-> r9c5 at least 4 greater than r8c5 -> r89c5 = [15]
-> r1c5 = 3 and r9c4 = 3

6. Max r6c9 = 7
-> NS r6c8 = 5
-> NS r6c9 = 7
-> NS r5c8 = 3
-> NS r5c7 = 1
-> NS r6c7 = 2
Also NP -> r5c12 = {25}
Also Since ?@r3c3 between +14 and +16 -> r5c3 cannot be 6
-> r5c3 = 9 and r5c9 = 6
-> r4c789 = [489] or [894]

7. NS r1c8 = 1
HS 7 in c8 -> r3c8 = 7

8. ?@r3c3 = Min +14 and Max +16
r4c123 = {367} and r5c3 = 9
-> Only possibility is ?@r3c3 = +16 = [169]
-> r4c12 = [37]

9. ?@r2c2 = Min +12 and Max +15
Since r4c2 = 7 -> Only possibility is ?@r2c2 = +15 = [357]

10. ?@r1c1 is Min +11 and Max +14 and does not contain any of (135)
-> Only possibilities are [246] and [248]
-> HS 9 in n1 -> r1c2 = 9
-> HS 6 in n1 -> r3c1 = 6
-> NP r12c3 = [78]

-> NS -> r2c8 = 9
-> r4c789 = [489]

Just cleanup from here


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 Post subject: Re: GE NC FO DGT 3
PostPosted: Wed Feb 19, 2014 10:18 am 
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Grand Master
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Joined: Wed Apr 30, 2008 9:45 pm
Posts: 694
Location: Saudi Arabia
Nice solution: I started with a lot of combo work on N1 and N9 which you avoided.


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 Post subject: Re: GE NC FO DGT 3
PostPosted: Fri Feb 21, 2014 4:59 am 
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Grand Master
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Joined: Wed Apr 23, 2008 6:04 pm
Posts: 1895
Location: Lethbridge, Alberta, Canada
Thanks HATMAN for another enjoyable puzzle!

HATMAN wrote:
Probably medium for Andrew - others may find it harder.
Thanks for the compliment! As I commented to HATMAN in a PM, this should have been "Probably medium for Andrew and wellbeback - others may find it harder." Having seen his walkthrough, I can see that this version was correct.

I started in the same way by listing the permutations for the digitised cages; then it was easier than expected. Then I solved in a similar way but working in a different order. I was a bit surprised that I didn't need to use some of the > relationships.

Here is my walkthrough for GE NC FO DGT 3:
1. Digitised cages have one cell value equal to the last digit of the cage total -> the other two cell values must total 10 = {19/28/37/46}, digitised cages can only contain 5 if the cage total is 15
1a. Digitised cage totals
11 = [137/146]
12 = [246]
13 = [139]
14 = [149/248]
15 = [159/258/357]
16 = [169/268]
17 = [179]
18 = [468]
19 = [379/469]

2. Digitised cages from R1C1 to R6C6 each have cage totals greater than the one to the left, the cage totals can only range between 11 and 19, the cage at R7C7 is greater than the one at R6C6 but isn’t digitised so can have a total greater than 19 -> cage at R1C1 = 11/12/13/14 … cage at R6C6 = 16/17/18/19
2a. No 5 in cage at R1C1
2b. No 5 in cage at R6C6

3. The cages at R7C8 and R7C9 have the same total -> cage at R7C7 must have an odd total = 17/19/21 (cannot total 23 which contains consecutive values) -> cages at R7C8 and R7C9 must total 12/13/14
3a. Non-consecutive cages totalling 12/13/14 must contain 1 or 2, which must be in R7C89 = {12}, locked for R7 and N9
3b. Cage at R7C8 is digitised and totals 12/13/14 -> R8C8 = {34}
3c. Non-digitised cage at R7C9 totals 12/13/14 -> R8C9 = {345}
3d. Non-digitised cage at R7C7 -> R7C7 = {345}
3e. Naked triple {345} in R7C7 + R8C89, locked for N9
3f. Non-consecutive fully ordered cages cannot contain both of 8,9 -> 8,9 in R9C789, locked for R9 and N9

4. From step 2, the maximum total for cage at R6C6 is 19 -> max total for cage at R3C3 is 16
4a. The first cells of the cages at R1C1, R2C2 and R3C3 are all in N1 and must be {123} (because 18 and 19 are the only digitised cages which can start with 4)
4b. The only digitised cage totalling 11…16 and starting with 3 is 15(3) = [357]
4c. Digitised cage at R3C3 cannot total 15 with 3 in R3C3, because cages at R1C1 and R2C2 would both require 4 in N1 -> cage at R2C2 must total 15 = [357] -> R2C2 = 3, R3C2 = 5, R4C2 = 7
4d. Digitised cage at R1C1 must total 11/12/14 -> R1C1 = {12}, R2C1 = 4, R3C1 = {6789}
4e. Digitised cage at R3C3 must total 16 -> R3C3 = {12}, R4C3 = 6, R5C3 = {89}
4f. Naked pair {12} in R1C1 + R3C3, locked for N1

5. Digitised cage at R3C3 totals 16 -> digitised cages at R4C4, R5C5 and R6C6 must total 17,18,19
5a. Digitised cage at R4C4 totals 17 = [179]
5b. Digitised cage at R5C5 totals 18 = [468]
5c. Digitised cage at R6C6 totals 19 = [379]
5d. Naked triple {258} is digitised cage at R4C5 -> R4C56 = [25], R5C6 = 8
5e. 4 in R4 only in R4C789, locked for N6

6. Digitised cage at R3C3 totals 16, R5C3 = 9 -> R3C3 = 1
6a. Naked pair {78} in R12C3, locked for C3 and N3
6b. Digitised cage at R1C1 totals less than 15, R1C1 = 2, R2C1 = 4 -> cage = [246] (only remaining permutation) -> R3C1 = 6, R1C2 = 9

7. 6 in R5 only in non-digitised cage at R5C7 = [136] (only remaining permutation) -> R5C12 = [52]

8. Digitised cage at R6C6 totals 19, non-digitised cage at R7C7 must be odd and greater so must total 21 = [579], R9C89 = [68]
8a. Non-digitised cage at R7C7 totals 21 -> equal cages at R7C8 and R7C9 must total 12
8b. Digitised cage at R7C8 = [246], R78C9 = [13]

9. Non-digitised cage at R6C7 = [257] (hidden triple in R6)

10. Non-digitised cage at R8C5 must contain 1 (R8C5 cannot be 5 because no 8,9 in R9C45) -> R8C5 = 1

11. 7,9 in C5 only in digitised cage at R1C5 = [379], R9C5 = 5 -> R9C4 = {23}, R12C3 = [78]

12. Digitised cage at R1C8 = [169] (only remaining permutation) -> R1C8 = 1, R2C78 = [69]

and the rest is naked singles.

Solution:
2 9 7 4 3 6 8 1 5
4 3 8 5 7 1 6 9 2
6 5 1 8 9 2 3 7 4
3 7 6 1 2 5 4 8 9
5 2 9 7 4 8 1 3 6
1 8 4 9 6 3 2 5 7
9 4 3 6 8 7 5 2 1
8 6 5 2 1 9 7 4 3
7 1 2 3 5 4 9 6 8


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