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 Post subject: Ix Killer 3
PostPosted: Sun Apr 12, 2015 10:25 pm 
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Joined: Sat Mar 28, 2015 8:36 pm
Posts: 24
Here is my next puzzle. A bit easier than the last one, but still enough difficulty to be interesting.

EDIT: After looking over my solve path again, I can't really say that this will be any easier to solve than the last one. Some steps would have been fairly tough to spot if I didn't have SSolver assisting.
ImageImage
SS Score: 1.25

Code: paste into solver:
3x3::k:2836:2835:0000:4364:0000:2320:0000:2837:2582:2835:2836:4364:4364:2053:2320:2320:2582:2837:5385:5385:3841:3841:2053:6146:6146:4367:4367:5385:2577:3841:3841:6916:6146:6146:3090:4367:2824:2824:2577:6916:6916:6916:3090:2567:2567:4874:2577:6400:6400:6916:3587:3587:3090:4366:4874:4874:6400:6400:2054:3587:3587:4366:4366:1306:1303:3851:3851:2054:5133:5133:2584:1049:1303:1306:0000:3851:0000:5133:0000:1049:2584:

Solution:
632954871
851763294
794128635
518247369
473695128
269831457
985312746
126479583
347586912

As with all my puzzles feedback and suggestions are welcome.


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 Post subject: Re: Ix Killer 3
PostPosted: Mon Apr 13, 2015 7:52 pm 
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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 ixsetf for your latest killer.

After some interesting early steps, thanks to totals being just right, I also had some difficulty in finding how to make progress in the later stages.

Here is my walkthrough for Ix Killer 3:
Prelims

a) 11(2) cage at R1C1 = {29/38/47/56}, no 1
b) 11(2) cage at R1C2 = {29/38/47/56}, no 1
c) 11(2) cage at R1C8 = {29/38/47/56}, no 1
d) 10(2) cage at R1C9 = {19/28/37/46}, no 5
e) R23C5 = {17/26/35}, no 4,8,9
f) R5C12 = {29/38/47/56}, no 1
g) R5C89 = {19/28/37/46}, no 5
h) R78C5 = {17/26/35}, no 4,8,9
i) 5(2) cage at R8C1 = {14/23}
j) 5(2) cage at R8C2 = {14/23}
k) 10(2) cage at R8C8 = {19/28/37/46}, no 5
l) 4(2) cage at R8C9 = {13}
m) 9(3) cage at R1C6 = {126/135/234}, no 7,8,9
n) 21(3) cage at R3C1 = {489/579/678}, no 1,2,3
o) 10(3) cage at R4C2 = {127/136/145/235}, no 8,9
p) 19(3) cage at R6C1 = {289/379/469/478/568}, no 1
q) 20(3) cage at R8C6 = {389/479/569/578}, no 1,2
r) 14(4) cage at R6C6 = {1238/1247/1256/1346/2345}, no 9

Steps resulting from Prelims
1a. Naked quad {1234} in R89C12, locked for N7
1b. Naked pair {13} in 4(2) cage at R8C9, locked for N9, clean-up: no 7,9 in 10(2) cage at R8C8
1c. 1 in N1 only in R123C3, locked for C3
1d. Min R7C12 = 11 -> max R6C1 = 8

2. 45 rule on C12 1 outie R5C3 = 3, clean-up: no 8 in R5C12, no 7 in R5C89
2a. 1 in N4 only in 10(3) cage at R4C2 = {136}, 1,6 locked for C2 and N4, clean-up: no 5 in R12C1, no 5 in R5C12, no 4 in R89C1
2b. 4 in N7 only in R89C2, locked for C2, clean-up: no 7 in R12C1, no 7 in R5C1

3. 45 rule on C89 1 outie R5C7 = 1, clean-up: no 9 in R5C89
3a. Killer pair 2,4 in R5C12 and R5C89, locked for R5
3b. 5 in R5 only in R5C456, locked for N5

4. 45 rule on C6789 3(2+1) innies R19C7 + R5C6 = 22
4a. Min R19C7 = 13, no 2,3 in R19C7

5. 45 rule on R5 2 outies R46C5 = 7 = {16/34}
5a. R23C5 = {17/26/35}, R78C5 = {17/26/35} -> combined cage R2378C5 = {17}{26}/{17}{35}/{26}{35}
5b. R46C5 = {34} (cannot be {16} which clashes with R2378C5), locked for C5 and N5, clean-up: no 5 in R2378C5
5c. Naked quad {1267} in R2378C5, locked for C5

6. 45 rule on R89 4(3+1) innies R8C5 + R9C357 = 31 can only be R8C5 = 7, R9C357 = 24 = {789}, locked for R9, R7C5 = 1, clean-up: no 2 in R8C8
6a. Naked pair {26} in R23C5, locked for N2

7. 9(3) cage at R1C6 = {135/234} (cannot be {126} because 2,6 only in R2C7), no 6
7a. 2 of {234} must be in R2C7 -> no 4 in R2C7
7b. 9(3) cage = {135/234}, CPE no 3 in R2C4

8. 3 in R7 only in R7C46, locked for N8
8a. 20(3) cage at R8C6 = {569} (only remaining combination), 9 locked for R8
8b. 20(3) cage = {569}, CPE no 5,6 in R8C4

9. 15(3) cage at R8C3 = {258/456}
9a. 8 of {258} must be in R8C3 -> no 8 in R8C4
9b. R8C4 = {24} -> no 2,4 in R9C4
9c. Naked pair {56} in R9C46, locked for R9 and N8 -> R8C6 = 9, R9C5 = 8, clean-up: no 4 in R8C8

10. 45 rule on C1234 3(2+1) innies R19C3 + R5C4 = 15
10a. Min R5C4 + R9C3 = 12 -> R1C3 = {12}
10b. Min R19C3 = 8 -> max R5C4 = 7

11. 25(4) cage at R6C3 = {2689/3589/3679/4579/4678} (cannot be {1789} because R7C4 only contains 2,3,4), no 1
11a. R7C4 = {234} -> no 2,4 in R6C34

12. 45 rule on N1 3 innies R123C3 = 1 outie R4C1 + 2
12a. Min R123C3 = 7 -> min R4C1 = 5
12b. Max R123C3 = 11, no 9 in R23C3

13. 3 in N1 only in one of the 11(2) cages = {38} (locking cages), 8 locked for N1
13a. Grouped X-Wing for 3 in 11(2) cages and 9(3) cage at R1C6, no other 3 in R12, clean-up: no 8 in 11(2) cage at R1C8, no 7 in 10(2) cage at R1C9

14. R19C7 + R5C6 = 22 (step 4), max R5C6 + R7C9 = 17 -> min R1C7 = 5
14a. 45 rule on whole grid 6 innies R19C357 = 39, R9C357 = 24 -> R1C357 = 15 = {159/258} (cannot be {168/267} because 6,7,8 only in R1C7), no 6,7, 5 locked for R1, clean-up: no 6 in R2C1, no 6 in R2C9
14b. 45 rule on R12 4(3+1) innies R1C357 + R2C5 = 21, R1C357 = 15 -> R2C5 = 6, R3C5 = 2, clean-up: no 4 in R1C9

15. 14(4) cage at R6C6 = {1238/1247/1256/1346/2345} -> R6C6 = {12}

16. 45 rule on R1234 6(3+3) innies R1C357 + R4C258 = 26, R1C357 = 15 -> R4C258 = 11 = {137/146/236} (cannot be {128/245} because 2,5,8 only in R4C8) -> R4C8 = {267}
16a. 12(3) cage at R4C8 = {129/147/156} -> R6C8 = {459}
16b. 45 rule on R6789 6(3+3) innies R6C258 + R9C357 = 38, R9C357 = 24 -> R6C258 = 14 = {149/356}
16c. 9 of {149} must be in R6C8 -> no 4 in R6C8, clean-up: no 7 in R4C8
16d. R4C258 = {146/236}, 6 locked for R4
16e. Killer pair 2,6 in R4C8 and R5C89, locked for N6

17. 27(5) cage at R4C5 = {34569/34578}
17a. 8 of {34578} must be in R5C6 -> no 7 in R5C6

18. 7 in C6 only in R34C6, locked for 24(4) cage at R3C6, no 7 in R34C7
18a. 24(4) cage contains 7 = {2679/3579/3678/4578}, no 1

19. Hidden killer pair 1,2 in R4C46 and R6C6 for N5, R6C6 = {12} -> R4C46 must contain one of 1,2
19a. Killer pair 1,2 in R4C258 and R4C46, locked for R4

20. 2 in C3 only in R12C3, locked for N1, clean-up: no 9 in 11(2) cages at R1C1 and R1C2
20a. 9 in N1 only in R3C12, locked for R3 and 21(3) cage at R3C1, no 9 in R4C1
20b. 21(3) cage contains 9 = {489/579}, no 6

21. R123C3 = R4C1 + 2 (step 12)
21a. R4C1 = {578} -> R123C3 = 7,9,10 must contain 1,2 = {124/126/127}, no 5

22. 45 rule on N9 3 innies R789C7 = 1 outie R6C9 + 14
22a. Min R6C9 = 3 -> min R789C7 = 17 but cannot be [269] which clashes with 10(2) cage at R8C8 -> no 2 in R7C7

23. R2C7 = 2 (hidden single in C7) -> R12C6 = 7 = {34} -> R67C6 = [12], R4C4 = 2 (hidden single in N5), R46C2 = [16], R4C8 = 6, R6C8 = 5 (cage sum), R8C8 = 8 -> R9C9 = 2, R5C8 = 2 (hidden single in C8) -> R5C9 = 8
23a. R9C2 = 4 (hidden single in R9) -> R8C1 = 1, R9C1 = 3, R8C2 = 2, R8C9 = 3, R9C8 = 1
23b. Clean-ups: no 8 in R12C2, no 9 in R1C8, no 9 in R1C9, no 5,9 in R2C9, no 9 in R5C12

24. Naked pair {47} in 11(2) cage at R1C8, locked for N3 -> R2C8 = 9, R1C9 = 1, R3C8 = 3 -> R34C9 = 14 = [59], R13C7 = [86], R34C6 = {78} -> R4C7 = 3 (cage sum)

and the rest is naked singles.

I loved the way the zero cells could be used for 45s! :D

Rating Comment:
I'll rate my walkthrough at 1.25. That seems a reasonable rating for the 6(3+3) innies steps. Maybe step 13 is technically in the 1.5 range, but it's so obvious that I won't take it into account for my rating.


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 Post subject: Re: Ix Killer 3
PostPosted: Fri Apr 17, 2015 11:49 pm 
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Joined: Wed Apr 16, 2008 1:16 am
Posts: 1044
Location: Sydney, Australia
Andrew wrote:
I also had some difficulty in finding how to make progress in the later stages.
Me too! Another really hard one. Loved it! Took ages to find out how to crack it. Different way to Andrew. Thanks ixsetf.

Start to Ix K3
11 steps:
Preliminaries
Cage 4(2) n9 - cells ={13}
Cage 5(2) n7 - cells only uses 1234
Cage 5(2) n7 - cells only uses 1234
Cage 8(2) n8 - cells do not use 489
Cage 8(2) n2 - cells do not use 489
Cage 10(2) n9 - cells do not use 5
Cage 10(2) n6 - cells do not use 5
Cage 10(2) n3 - cells do not use 5
Cage 11(2) n1 - cells do not use 1
Cage 11(2) n1 - cells do not use 1
Cage 11(2) n4 - cells do not use 1
Cage 11(2) n3 - cells do not use 1
Cage 9(3) n23 - cells do not use 789
Cage 21(3) n14 - cells do not use 123
Cage 10(3) n4 - cells do not use 89
Cage 20(3) n89 - cells do not use 12
Cage 19(3) n47 - cells do not use 1
Cage 14(4) n5689 - cells do not use 9

No clean-up done unless stated.
1. "45" on r89: 4 innies r8c5 + r9c357 = 31
1a. max. r9c357 = 24 -> min. r8c5 = 7
1b. -> r8c5 = 7, r7c5 = 1
1c. r8c5 = 7 -> r9c357 = 24 = {789} only: all locked for r9

2. "45" on whole grid: 6 zero cells r19c357 = 39.
2a. r9c357 = 24 -> r1c357 = 15 (no eliminations yet
2b. "45" on r12: 4 innies r1c357 + r2c5 = 21. r1c357 = 15 -> r2c5 = 6, r3c5 = 2

3. Naked quad {1234} in r89c12: all locked for n7

4. 4(2)n9 = {13} only: both locked for n9

5. 3 in r7 only in n8: locked for n8

6. 5 in r9 only in n8: locked for n8

7. "45" on c89: 1 outie r5c7 = 1

8. "45" on c12: 1 outie r5c3 = 3

9. "45" on r5: 2 remaining outies r46c5 = 7 = {34} only: both locked for c5 and n5
9a. -> 17(5)n5 = 34{569/578}(no 2)
9b. must have 5: 5 locked for r5 and n5

10. 20(3)r8c6 = {569} only combination.

11. 9(3)r1c6 = {135/234}
11a. 14(4)r6c6 = {1238/1247/1256/1346/2345} 11b. but {2345} is blocked: like this
i. 9(3)r1c6 + 14(4) cannot be [55] since that would leave no 5 for the 20(3)r8c6
ii.-> {2345} in 14(4) must have {234} in 9(3)
iii. but {34} in r12c6 clashes with r67c6 = [2](34)
11c. -> 14(4)r6c6 = {1238/1247/1256/1346}
11d. must have 1 -> r6c6 = 1
11e. -> 9(3)r1c6 = {234} only -> r2c7 = 2, r12c6 = {34} only: both locked for n2 and c6

Much easier now. Just lots of cage clean-ups and some more obvious "45"s which Andrew uses (if you need a hint).
Cheers
Ed


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 Post subject: Re: Ix Killer 3
PostPosted: Sun Apr 19, 2015 5:43 pm 
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Joined: Tue Jun 16, 2009 9:31 pm
Posts: 282
Location: California, out of London
Thanks ixsetf. Here's how I started...
Hidden Text:
1. Innies r89 -> r8c5 + r9c357 = +31.
Max r8c5 = 7
-> r8c5 = 7 and r9c357 = {789}
-> r7c5 = 1
-> (Innies r34567 = r37c5 = +3) -> 8(2)n2 = [62]

2. Outies c12 -> r5c3 = 3
1 in n1 only in r123c3
-> 1 in n4 only in r46c2
-> 10(3)n2 = [136] or [631]
Also 2 * 5(2) in n7 -> 1 in r89c1
-> 4 in r89c2
Also since 4(2)in n9 = {13}
-> r89c1 = {13} and r89c2 = {42}

3. Outies c89 -> r5c7 = 1
-> Innies r5 -> r5c456 = +20
-> r46c5 = +7 = {34}
-> r5c456 = {578} or {569}

4. Given r7c5 = 1 -> Innies r67 = r6c258 = +14
Given r3c5 = 2 -> Innies r34 = r4c258 = +11
Given r46c2 = {16} and r46c5 = {34} -> only possibilties for r4c258, r6c258, and r5 are:

a) r4c258 = [146], r6c258 = [635], r5 = [47][3]{569}[1]{28}
b) r4c258 = [632], r6c258 = [149], r5 = [29][3]{578}[1]{46}

5. 3 in n1 in r12c2
-> 8 in n1 in r12c1
-> 8 in n4 in r46c3
-> HS 8 in c2n7 -> r7c2 = 8
-> r9c3 from (79)

6. Innies c34 -> r1c3 + r5c4 + r9c3 = +15
Since Min r9c3 = 7 and Min r5c4 = 5 -> Max r1c3 = 3
Since 3 already in c3 -> r1c3 from (12)
Given r2c5 = 6 -> Innies r12 = r1c357 = +15
-> Min r1c7 = 4

7. 3 in r7 in r6c46
10(2)n9 either {46} or [82]
-> One of (24) in r7c46.
-> Both r7c4 and r7c6 from (234)

8! The number 2
2 in n6 in r4c8 or r5c89
-> 2 in c7 only in r2c7 or r7c7.
In the former case r12c6 = {34} which puts r7c6 = 2
-> 2 in r7c67

Also since max r7c4 = 4 -> All other cells in 25(4) are Min 5.
-> HS 2 in r6 -> r6c1 = 2

8. -> r7c1 = 9
-> r9c3 = 7
-> r78c3 = {56}
-> r4c1 = 5
-> r3c12 = [79]
Also 11(2)n4 = [47], r456 = {569}, 10(2)r5 = {28}
Also r46c3 = {89}
-> r123c3 = {124}
etc.


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