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Ed
 Post subject: Assassin 319
PostPosted: Fri May 29, 2015 10:28 pm 
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Joined: Wed Apr 16, 2008 1:16 am
Posts: 1043
Location: Sydney, Australia
9 years of Assassins and 7 years here! Great achievement. Feeling the need for a break so my last puzzle for a while. They take a ridiculous number of hours to get ready. This one was no exception. Had to use a couple of advanced steps that took ages to find. Gets an SS score of 1.65.

Assassin 319

Image
code: paste into solver:
3x3::k:5632:3585:3585:4098:4098:1795:1795:6148:6148:5632:5632:3585:3585:2821:2821:6406:6148:6148:5127:5127:2824:2824:2821:6406:6406:6406:1801:5127:2570:2570:2824:5899:5899:6406:3340:1801:5127:5389:5389:6670:5899:5899:3340:3340:2575:7696:5389:6670:6670:6670:3601:3601:6930:2575:7696:5395:5395:6670:2324:2325:3601:6930:6930:7696:5395:5395:2324:2324:2325:5398:3607:6930:7696:7696:7696:7696:5398:5398:5398:3607:3607:
solution: 
+-------+-------+-------+
| 8 4 1 | 9 7 5 | 2 6 3 |
| 9 5 3 | 6 1 2 | 4 7 8 |
| 7 2 6 | 4 8 3 | 9 1 5 |
+-------+-------+-------+
| 6 3 7 | 1 5 9 | 8 4 2 |
| 5 9 4 | 8 2 7 | 6 3 1 |
| 1 8 2 | 3 6 4 | 7 5 9 |
+-------+-------+-------+
| 2 1 5 | 7 4 8 | 3 9 6 |
| 4 6 9 | 2 3 1 | 5 8 7 |
| 3 7 8 | 5 9 6 | 1 2 4 |
+-------+-------+-------+
Cheers
Ed
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Afmob
 Post subject:
PostPosted: Sat May 30, 2015 10:40 am 
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Joined: Mon Apr 21, 2008 9:44 am
Posts: 310
Location: MV, Germany
Thanks for this new Killer, Ed! I found some advanced moves available (e.g. Locking out cages in C9) but they weren't necessary, so my walkthrough has a rather low rating.

A319 Walkthrough:
1. R123
a) Innies R12 = 7(3) = {124} locked for R2
b) 16(2) = {79} locked for R1+N2
c) 22(3) = 9{58/67} -> 9 locked for R2+N1
d) 24(4) = 78{36/45} -> 7 locked for R2+N3; 8 locked for N3
e) 22(3) = {589} locked for N1

2. C789 !
a) Innies C89 = 8(3) = 1{25/34} -> 1 locked for C8
b) 27(4) = 9{378/468/567} -> CPE: R89C8 <> 9
c) R78C9 <> 9 since it sees all 9 of C8
d) ! 14(3) @ R9 <> 9 since {23}9 blocked by Killer pair (23) of Innies C89
e) 9 locked in 10(2) @ C9 = {19} locked for C9+N6
f) Hidden Single: R3C8 = 1 @ C8, R3C7 = 9 @ N3, R7C8 = 9 @ C8
g) Outie C89 = R5C7 = 6
h) Both 7(2) <> 1,6
i) 6 locked in 24(4) @ N3 = {3678} locked for N3

3. R123
a) 8 locked in R3C456 @ R3 for N2
b) 1 locked in 11(3) @ R2 = 1{28/46} -> R3C5 = (68)
c) Both 7(2): R1C6+R4C7 <> 4

4. R789+C7 !
a) Innies N8 = 27(4) = 9{378/468/567} <> 1,2 -> 9 locked for R8
b) Outies N7 = 6(2) = [15/24]
c) Innies N8 = 69{48/57} since R9C4 = (45) -> 6 locked for N8, R7C4+R9C56 <> 4,5
d) 21(4) can only have two of (6789) -> R89C7 <> 7,8
e) 9 locked 21(4) @ N8 for R9 = 9{138/147/156/237} since 49{26/35} blocked by R12C7 = (245)
f) 21(4) = 19{38/47/56} <> 2 since {2379} blocked by Killer pair (23) of 14(3) @ R9 -> 1 locked for C7
g) ! Hidden Killer pair (78) in 14(3) + R4C7 for C7 since 14(3) can only have one of them -> R4C7 = (78); R6C6 <> 6,7,8,9 since R67C7 <> 1,6

5. R123 !
a) ! Outies R12 = 19(2+1): R3C6 <> 6,8 since R3C5 = (68) and R4C7 <> 5
b) 25(5) = 189{25/34} since R2C7 = (24) -> R4C7 = 8; R3C6 = (35)
c) Hidden Killer pair (48) in R3C4 @ N2 since 11(3) @ R2 can only have one them -> R4C8 = (48)
d) 11(3) @ N1 <> 3,7 since R3C4 = (48); R3C3+R4C4 <> 4
e) 1 locked in 14(4) @ R1 = {1346} since {126}5 blocked by R3C3 = (26) -> 4 locked for R1+N1; 3,6 locked for R2
f) 7(2) @ R1 = {25} locked for R1
g) 2 locked in R3C123 @ N1 for R3
h) 7(2) @ R3 = [43/52]

6. C789+N1
a) 2 locked in R12C7 @ N3 for C7
b) 2 locked in 14(3) @ N9 @ R9 = 2{48/57}
c) 6 locked in 27(4) @ N9 = 69{48/57} -> 6 locked for C9
d) R1C1 = 8, R1C9 = 3, R4C9 = 2 -> R3C9 = 5, R3C6 = 3 -> R2C7 = 4, R2C4 = 6, R3C5 = 8, R3C4 = 4, R9C4 = 5, R4C4 = 1 -> R3C3 = 6
e) 20(4) = {2567} since R3C1 = (27) -> R5C1 = 5, R4C1 = 6

7. N489
a) Hidden pair (12) locked in R6C13 @ N4 for R6; R6C3 = (12)
b) 14(3) @ N5 = {347} -> R6C6 = 4; 3 locked for C7
c) 9(3) = {234} locked for N8
d) 9(2) = {18} locked for C6+N8
e) R9C7 = 1, R8C7 = 5
f) 14(3) = {248} locked for N9

8. Rest is singles.

Rating:
Hard 1.0 - Easy 1.25. I used two Hidden Killer pairs and CPE.
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Andrew
 Post subject: Re: Assassin 319
PostPosted: Tue Jun 02, 2015 8:13 pm 
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Grand Master
Grand Master

Joined: Wed Apr 23, 2008 6:04 pm
Posts: 1894
Location: Lethbridge, Alberta, Canada
Thanks Ed for your latest Assassin and, as you said, your last for a while. Your Assassins and other puzzles have been greatly appreciated. :D By my count you've posted more than 100 V1 Assassins, starting with uA95, even more than Ruud's 91. :applause: Enjoy your life and I hope that you'll have time to solve some puzzles and post your walkthroughs.

I also found some advanced steps, but managed to solve this Assassin without using them.

Here is my walkthrough for Assassin 319:
Prelims

a) R1C45 = {79}
b) R1C67 = {16/25/34}, no 7,8,9
c) R34C9 = {16/25/34}, no 7,8,9
d) R4C23 = {19/28/37/46}, no 5
e) R56C9 = {19/28/37/46}, no 5
f) R78C6 = {18/27/36/45}, no 9
g) 22(3) cage at R1C1 = {589/679}
h) 11(3) cage at R2C5 = {128/137/146/236/245}, no 9
i) 11(3) cage at R3C3 = {128/137/146/236/245}, no 9
j) 21(3) cage at R5C2 = {489/579/678}, no 1,2,3
k) 9(3) cage at R7C5 = {126/135/234}, no 7,8,9
l) 14(4) cage at R2C2 = {1238/1247/1256/1346/2345}, no 9
m) 27(4) cage at R6C8 = {3789/4689/5679}, no 1,2

Steps resulting from the Prelims
1a. Naked pair {79} in R1C45, locked for R1 and N2
1b. 22(3) cage at R1C1 = {589/679}, 9 locked for R2 and N1
1c. 6 of {679} must be in R1C1 -> no 6 in R2C12
1d. 9 in N3 only in R3C78, locked for 25(5) cage at R2C7, no 9 in R4C7
1e. 27(4) cage at R6C8 = {3789/4689/5679}, CPE no 9 in R89C8

2. 45 rule on N7 2 outies R6C1 + R9C4 = 6 = {15/24}
2a. 30(7) cage at R6C1 must contain 3, locked for N7

3. 45 rule on R12 1 outie R3C5 = 1 innie R2C7 + 4 -> R2C7 = {124}, R3C5 = {568}
3a. 11(3) cage at R2C5 = {128/146/236/245}
3b. R3C5 = {568} -> no 5,6,8 in R2C56
3c. 11(3) cage = {128/146/245} (cannot be {236} = {23}6 which clashes with R2C7 + R3C5 = [26], IOD clash), no 3
3d. Naked triple {124} in R2C567, locked for R2
[This IOD clash wouldn’t have been necessary if I’d spotted 45 rule on R12 3 innies R2C567 = 7 = {124}, locked for R2.]

4. 45 rule on C89 1 outie R5C7 = 1 innie R3C8 + 5 -> R5C7 = {6789}, R3C8 = {1234}
4a. 13(3) cage at R4C8 can only contain one of 6,7,8,9, R5C7 = {6789} -> no 6,7,8,9 in R45C8
4b. R3C7 = 9 (hidden single in N3), clean-up: no 4 in R3C8
4c. 9 in C8 only in R67C8, locked for 27(4) cage at R6C8, no 9 in R78C9

5. 24(4) cage at R1C8 = {3678/4578}, no 1,2, 7 locked for R2
5a. 22(3) cage at R1C1 = {589} (only remaining combination), locked for N1
5b. 8 in R3 only in R3C456, locked for N2

6. 14(4) cage at R2C2 = {1256/1346/2345}
6a. 1,2,4 only in R1C23 -> R1C23 = {12/14/24}, no 3,6
6b. Killer triple 1,2,4 in R1C23 and R1C67, locked for R1
6c. 24(4) cage at R1C8 (step 5) = {3678} (only remaining combination), locked for N3, clean-up: no 1,4 in R1C6, no 1,4 in R4C9, no 8 in R5C7 (step 4)

7. 45 rule on C89 3 innies R345C8 = 8 = {125/134}, 1 locked for C8

8. 45 rule on N4 4 innies R456C1 + R6C3 = 14 = {1238/1256/1346/2345} (cannot be {1247} which clashes with 21(3) cage at R5C2), no 7,9

9. 45 rule on N8 4 innies R7C4 + R9C456 = 27 = {4689/5679} (cannot be {3789} because no 3,7,8,9 in R9C4), no 1,2,3, 6 locked for N8, clean-up: no 3 in R78C6
9a. Killer pair 4,5 in 9(3) cage at R7C5 and R9C4, locked for N8
9b. R9C4 = {45} -> R6C1 = {12} (step 2)
9c. 21(4) cage at R8C7 cannot contain more than two of 6,7,8,9 -> no 6,7,8 in R89C7

10. 25(5) cage at R2C7 contains 9 = {12589/12679/13489/14569/23479} (cannot be {13579/23569} because R2C7 + R3C8 only contain 1,2,4)
10a. 25(5) cage only contains two of 1,2,4 -> no 1,2,4 in R3C6 + R4C7

11. 45 rule on C1234 2 outies R16C5 = 1 innie R8C4 + 11, min R16C5 = 12 -> min R6C5 = 3

[I ought to have spotted this earlier.]
12. 14(3) cage at R8C8 = {248/257/347/356} (cannot be {149} because 1,9 only in R9C9, cannot be {158/167} which clash with 27(4) cage at R6C8, cannot be {239} which clashes with R345C8), no 1,9
12a. R7C8 = 9 (hidden single in N9)
12b. 9 in C9 only in R56C9 = {19}, locked for C9 and N6, clean-up: no 6 in R4C9
12c. R3C8 = 1 (hidden single in C8) -> R5C7 = 6 (step 4), clean-up: no 6 in R1C6, no 5 in R3C5 (step 3)
12d. Min R3C34 = 5 -> max R4C4 = 6
12e. 6 in R1 only in R1C89, locked for N3
12f. 9 in N8 only in R9C56, locked for R9

13. Hidden killer pair 7,8 in R4C7 and R67C7 for C7, 14(3) cage at R6C6 cannot contain both of 7,8 -> R4C7 = {78}, 14(3) cage must contain one of 7,8 in R67C7 -> no 7,8,9 in R6C6
13a. 25(5) cage at R2C7 (step 10) contains 1,9 = {12589/12679/13489} (cannot be {14569} which doesn’t contain 7 or 8)
13b. R3C5 = R2C7 + 4 (step 3)
13c. 25(5) cage at R2C7 = {12589/13489} (cannot be {12679} which clashes with R2C7 + R3C5 = [26], IOD clash) -> R4C7 = 8, R3C6 = {35}, clean-up: no 2 in R4C23
13d. 7 in N6 only in R6C78, locked for R6

14. 14(3) cage at R6C6 contains 7 = {167/257/347}
14a. 6 of {167} must be in R6C6 -> no 1 in R6C6

15. 27(4) cage at R6C8 = {3789/4689/5679}
15a. 4 of {4689} must be in R6C8 -> no 4 in R78C9

16. 45 rule on N3 3(2+1) remaining outies R13C6 + R4C9 = 10 must form combination {235} because these cells only contain 2,3,5, CPE no 2,3,5 in R4C6

17. Hidden killer pair 2,4 in R34C9 and R9C9 for C9, R34C9 contains one of 2,4 -> R9C9 = {24}
17a. 14(3) cage at R8C8 (step 12) = {248/257/347} (cannot be {356} which doesn’t contain 2 or 4), no 6
17b. R1C8 = 6 (hidden single in C8)
17c. 6 in N9 only in R78C9 -> 27(4) cage at R6C8 = {4689/5679} (cannot be {3789} which doesn’t contain 6), no 3

18. 14(3) cage at R8C8 (step 17a) = {248/347} (cannot be {257} = {57}2 which clashes with 13(3) cage at R4C8 + R6C8, killer ALS block), no 5, 4 locked for N9

19. 9 in R9 only in R9C56 -> 21(4) cage at R8C7 = {1389/1569} (cannot be {2379} which clashes with 14(3) cage at R8C8), no 2,7, 1 locked for C7
19a. 14(3) cage at R6C6 (step 14) = {257/347}, no 6

20. R4C9 = {235}, 13(3) cage at R4C8 = {256/346} -> R45C8 = {25/34}
20a. Combined half cage R45C8 + R4C9 = {25}3/{34}2/{34}5, 3 locked for N6
20b. 3 in C7 only in R789C7, locked for N9
20c. 14(3) cage at R8C8 (step 18) = {248} (only remaining combination), locked for N9
20d. 27(4) cage at R6C8 (step 17c) = {5679} (only remaining combination), CPE no 5 in R4C9, clean-up: no 2 in R3C9
20e. 2 in N3 only in R12C7, locked for C7
20f. 5 in C8 only in R456C8, locked for N6

21. 1 in R1 only in 14(4) cage at R2C2 (step 6) = {1346} (cannot be {1256} = {12}65 which clashes with R13C6, killer ALS block) -> R1C23 = {14}, locked for R1 and N1, R2C34 = {36}, locked for R2
21a. R1C9 = 3 (hidden single in N3), R1C1 = 8 (hidden single in R1), R4C9 = 2, R9C9 = 4, R3C9 = 5, R1C67 = [52], R2C7 = 4, R6C7 = 7, R6C8 = 5, R3C6 = 3, R2C34 = [36], R3C5 = 8, clean-up: no 7 in R4C2
21b. Naked pair {28} in R89C8, locked for C8 -> R2C89 = [78]
21c. Killer pair {12} in R2C6 and R78C6, locked for C6

22. R9C56 = {69} (hidden pair in N8), 6 locked for R9
22a. R9C56 = {69} = 15 -> R89C7 = 6 = {15}, locked for C7 -> R7C7 = 3, R6C6 = 4

23. R9C4 = 5 -> R6C1 = 1 (step 2), R56C9 = [19], clean-up: no 9 in R4C23
23a. Killer pair 3,4 in R4C23 and R4C8, locked for R4
23b. R4C4 = 1, R3C4 = 4 (hidden single in N2) -> R3C3 = 6 (cage sum)
23c. R3C12 = {27} = 9 -> R45C1 = 11 = [65], R2C12 = [95], clean-up: no 4 in R4C23
23d. R4C23 = [37]
23e. R6C2 = 8, R6C345 = [236] = 11 -> R57C4 = 15 = {78}, locked for C4, R8C4 = 2

24. R4C56 = [59] = 14 -> R5C56 = 9 = [27]

and the rest is naked singles.

Rating Comment:
I'll rate my walkthrough at 1.25. I used hidden killer pairs, IOD clashes, CPEs and a combined half cage.
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HATMAN
 Post subject: Re: Assassin 319
PostPosted: Wed Jun 03, 2015 7:39 pm 
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Grand Master
Grand Master

Joined: Wed Apr 30, 2008 9:45 pm
Posts: 694
Location: Saudi Arabia
Well done Ed.

Enjoy your break, I'll post one from my store tomorrow and ixsetf has just contacted me to say he will be posting a few.

Cheers

Maurice
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