Assassin 89

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sublue
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Assassin 89

Post by sublue »

Woo Hoo! Gotta love that Central Time Zone! I don't rate puzzles with a number scale, but put this one down as disturbingly easy. Is this really Ruud's site?

Afmob tells me that the sign error in Step 20 requires all subsequent steps to be re-done. I don't have time for that, so keep it in mind if you are using this walkthru. My apologies.
Editted once to correct sign error (thanks Afmob!) and to add lines for readability.Prelims:
a) N1: 11(2) no 1
b) N14: 19(3) no 1
c) N2: 14(4) no 9
d) N23: 21(3) no 1,2,3
e) N23: 13(2) no 1,2,3
f) N3: 11(3) no 9
g) N4:10(3) no 8,9
h) N4: 20(3) no 1,2
i) N69: 22(3) no 1,2,3,4
j) N78: 7(2) no 7,8,9
k) N78: 19(2) no 1
l) N89: 10(3) no 8,9
m) N9: 9(2) no 9

Assumption: I assume Row, Column, Nonet and/or Cage cleanups after each step that results in any locked or placed digits. Other cleanups are noted as sub-steps.

Solving:
1) N69: 22(3): 9 locked in cage and C7
a) R1C6 no 4

2) N14: 1 innie : R2C3 = 1
a) R23C4 no 2,3

3) N69: 1 innie: R8C7 = 3
a) R78C6 no 4,7

4) N3: 2 outies: R23C6 = 17 &#61672; R23C6 = {89} locked for N2, C6
a) R3C7 no 6,7,8
b) R23C4 = {67} locked for N2, C4

5) N2: 14(4) combo analysis: no 1
a) R3C5 = 1

6) N3: 9 locked in 17(3) &#61672; no 4,7,8

7) N3: 1 locked in R1C89 of 11(3) &#61672; no 5 in 11(3)

8) N7: 2 outies: R78C4 = 13 &#61672; R7C4 no 1,2,3; R8C4 no 2,4,5
a) R7C3 no 4,5,6

9) C6789: 2 innies: R19C6 = 9 &#61672; R9C6 no 1,2,3

10) C1234: 2 innies: R19C4 = 5 &#61672; R1C4 no 5; R9C4 no 4,5,8,9

11) C89: 2 outies: R49C7 = 3 &#61672; R49C7 = {12}
a) R9C8 no 1,2,4,5,6
b) N6: 16(3) combo analysis: R4C89 no 1,2,3,4

12) C7: 4 locked into R123C7 for C7 and N3
a) N3: 11(3) no 6

13) C12: 2 outies: R16C3 = 12 &#61672; R1C3 no 2,6; R6C3 no 6
a) R2C1 no 5,9

14) N5: 1 outie: R7C5 = 7


15) C6: 7 locked in R456C7 &#61672; 12(3) no 5,6

16) N8: 3 locked in R9C45 for N8, R9

17) R1: 9 locked in R1C13 for N1, R1

18) N1: 1 innie and 1 outie: R3C3 = R4C2 +4 &#61672;R4C2 no 5,6,7,8,9; R3C3 no 2,3,4

19) N9: 1 innie and 1 outie: R7C7 = R6C8 + 6 &#61672; R6C8 no1,4,5,6,7,8,9; R7C7 no 5,6

20) C9: 2 innies and 2 outies: R34C9 - 7 = R15C8
a) Max R15C8 = 17 &#61672; max R34C9 = 10 &#61672; R4C9 no 9, R3C9 no 6,9

21) C8: 9 locked into R23C8 for 17(3) cage, N3 and C8
a) R23C8 no 2

22) N6: 16(3) combo analysis: {[1]78/[2]68} &#61672; R4C89 no 5 and 8 locked into R4C89 for 16(3) cage, N6, R4

23) R1: 2 innies and 2 outies: R1C17 = R2C59 + 9
a) Max R1C17 = 17 &#61672; max R2C59 = 8 &#61672; R2C9 no 7,8
b) Min R2C59 = 5 &#61672; min R1C17 = 14 &#61672; R1C1 no 2,3,4,5; R1C7 no 4

24) N3: 11(3) combo analysis: R1C89 no 2,3

25) C9: 2 locked in R23C9 for C9

26) N6: 4 locked into 13(3) cage &#61672; no 1,5,9 in 13(3) cage.

27) N6: 5 locked into R56C7 and step 1 &#61672; 22(3) = {589}
a) R7C7 = 8, R56C7 = {59} locked for C7
b) R3C7 = 4 NS &#61672; R3C6 = 9
c) R2C6 = 8

28) N9: NS R9C8 = 7 &#61672; R9C7 = 2
a) R4C7 = 1

29) N6: 16(3) combo analysis: R4C9 = 7 and R4C8 = 8

30) N3: R1C8 = 1 NS &#61672; R1C9 = 8 &#61672;R2C9 = 2

31) N3: 17(3) Combo analysis: R23C8 no 6 &#61672; R3C89 = {35} locked for N3, R3 &#61672; R2C8 = 9 NS

32) N1: 11(2) Combo analysis: R1C23 no 3

33) N2: 3 locked into R1C456 &#61672; R2C5 no 3

34) R2: {67} NP at R2C47 locked for R2

35) N2: 2 locked in R1C456 for R1 &#61672; R1C3 no 9

36) N1: R1C1 = 9 HS &#61672; 15(3) combo analysis: R2C1 = 4; R3C1 = 2

37) N2: R2C5 = 5 NS

38) N1: R1C3 = 5 NS &#61672; R1C2 = 6

39) N1: R2C2 = 3 NS &#61672; 14(3) Combo Analysis: R3C2 = 7, R4C2 = 4

40) Cleanup Naked Singles: R3C3 = 8, R3C4 = 6, R2C4 = 7, R12C7 = [76]

41) N4: 1 locked into R5C12 for 10(3), R5
a) 10(3) no 5
b) N4: 5 locked into R6C12 for 20(3) and R6
c) 20(3) no 3
d) R6C7 = 9 NS
e) R5C7 = 5 NS
f) R6C3 = 7 NS
g) R6C1 no 6 &#61672; R6C12 ={58} locked for R6

42) N5: R4C4 = 5 HS
a) R7C4 = 4 NS &#61672; R7C3 = 3

43) N5: 6 locked into R456C5 for 27(5) N5 and C5

44) Cleanup Hidden Singles: R9C1 = 7, R5C6 = 7

45) N14: 19(3) R45C3 = {29} locked for N4 and C3

46) N5: R5C2 = 1 NS &#61672; R45C1 = {36} locked for C1

47) N78: 19(3) has R89C3 = {46} locked &#61672; R8C4 = 9

48) C4: R5C4 = 8 HS

49) Rest of puzzle is a cascade of Naked Singles.

965234718
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278619435
349562187
612897543
857143926
523471869
784926351
196385274
Last edited by sublue on Sat Feb 09, 2008 7:31 pm, edited 2 times in total.
Susan
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Post by HATMAN »

Susan

I agree - managed it in one session over my (early) lunch.
Save a GRUE: eat a brass lantern
Afmob
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Post by Afmob »

I can't say that this assassin was "disturbingly" easy or moderate. I guess I missed something since I used a chain to crack it.

A89 Walkthrough:

1. C1234
a) Innies N14 = 1 = R2C3
b) 7(2): R7C4 <> 6
c) Outies N7 = 13(2) = [49/58]
d) 7(2) = [25/34]
e) Innies = 5(2) = {14/23}

2. N23
a) Innies = 1 = R3C5
b) 14(4) = {2345} locked for N2
c) 14(3) = {167} -> 6,7 locked for C4+N2
d) Naked pair (89) locked in R23C6 for C6
e) 13(2) = [85/94]
f) Innies N3 = 17(3) = 4{58/67} -> 4 locked for C7+N3
g) 9 locked in 17(3) = 9{26/35}
h) 1 locked in 11(3) = 1{28/37}

3. C6789
a) Innies N69 = 3 = R8C7
b) Hidden pair (12) in R49C7 for C7 -> no other candidates
c) 9(2) = [18/27]
d) 16(3) = {169/178/259/268}; R4C89 <> 1,2
e) 10(3) = {16/25}3
f) 12(3) <> 6 because 6{15/24} blocked by Killer pairs (26,56) of 10(3)
g) 6 locked in R789C6 for N8
h) Innies = 9(2): R9C6 <> 1,2,3

4. N589
a) Outies N5 = 7 = R7C5
b) 3 locked in 18(4) for R9
c) 6 locked in 27(5) = 167{49/58}
d) 7 locked in 12(3) = 7{14/23}

5. N369
a) Innies+Outies N9: -6 = R6C8 - R7C7 -> R7C7 = (89), R6C8 = (23)
b) Killer pair (12) locked in 9(2) + 14(3) for N9
c) 13(3) @ N9 = {247/256/346}
d) 14(3) <> 6 because {167} blocked by Killer pair (67) of 13(3) @ N9
e) 6 locked in 13(3) @ N9 = 6{25/34} -> 6 locked for C8
f) 4 locked in 13(3) @ R5C8 = 4{18/27/36}

6. C123
a) 9 locked in R1C123 for N1
b) Innies N1 = 18(3) = {378/468/567}
c) Innies+Outies N1: -4 = R4C2 - R3C3 -> R3C3 <> 3,4; R4C2 = (1234)
d) 11(2) <> {47} since it's a Killer pair of Innies N1
e) Outies C12 = 12(2) = [39/57/84/93]
f) 11(2): R1C2 <> 5,9

7. R123
a) Killer quad (2345) locked in 11(2) + R1C456 for R1
b) 11(3) must have 2 xor 3 and it's only possible @ R2C9 -> R2C9 = (23)
c) 15(3) <> {267} since it's blocked by Killer pair (67) of Innies N1
d) 15(3) must have 6,7,8 xor 9 and R1C1 = (6789) -> R23C1 <> 6,7,8
e) 21(3): R2C7 <> 8 because R1C7 <> 4
f) 8 locked in R1C789 for R1
g) 11(2) = [29/65]
h) Killer pair (25) locked in 15(3) + 11(2) for N1
i) Innies+Outies N1: -4 = R4C2 - R3C3 -> R4C2 = (234)
j) 14(3) = 4{28/37} -> 4 locked for C2

8. C123
a) 14(3): R4C2 <> 3 because {47}3 blocked by Killer pair (47) of 15(3)
b) Innies+Outies N1: -4 = R4C2 - R3C3 -> R3C3 <> 7
c) Outies C12 = 12(2) = [57/93]
d) 20(3) <> 6 because R6C3 = (37); R6C12 <> 3,7
e) 19(3) @ N1 <> 3 because {379} blocked by R6C3 = (37)
f) Innies N7 = 13(3) <> 9 because R789C3 <> 1

9. N36
a) 17(3): R3C9 <> 2,9 because R23C8 <> 6 and Killer pair (35) of 13(3) @ R6C8 blocks {35}9
b) 9 locked in 17(3) for C8
c) Innies N3 = 17(3): R2C7 <> 5 because 21(3) can't have 5 and 8

10. R123 !
a) ! Consider candidates of R3C3 -> R3C9 <> 6
- i) R3C3 = 6 -> R3C9 <> 6
- ii) R3C3 = 8 -> R2C6 = 8 (HS @ N2) -> 21(3) = 8{67} -> R3C9 <> 6
b) 17(3) = {359} locked for N3
c) Innies N3 = {467} -> R3C7 = 4; {67} locked for C7+N3

11. N69
a) 22(3) = {589} -> 5 locked for N6
b) 16(3) = 8{17/26} because R4C8 = (78) -> 8 locked for R4+N6
c) 13(3) @ R5C8 = 4{27/36}
d) 1 locked in 16(3) = {178} -> R4C7 = 1; 7 locked for R4+N6
e) 13(3) @ R5C8 = {346} locked for N6
f) 9(2) = [27] -> R9C7 = 2, R9C8 = 7
g) 13(3) @ R6C8 = {256} -> R6C8 = 2, {56} locked for C8+N9

12. N17
a) Hidden Single: R3C1 = 2 @ R3
b) 15(3) = {249} -> R1C1 = 9, R2C1 = 4
c) 17(3) = {179} -> R8C1 = 7, R9C1 = 1, R9C2 = 9

13. Rest is singles.

Rating: Easy 1.5. I had to use a small chain to crack it.
Last edited by Afmob on Thu Feb 14, 2008 8:17 am, edited 2 times in total.
gary w
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Post by gary w »

Yes,much easier than last week's.

once the various prelims are in place and you can place r3c3=5/6/7/8/9 then the other combos in r3 and N4 mean that 13(2) cage N2/3 must be 94 after which it's a straightforward mop-up.

Can't relax with av2 threatened though!!

Regards

Gary
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Post by mhparker »

Ruud wrote:I hope there will be time in the weekend to create a good V2.
I know what you mean! I'm pretty busy at work at the moment, too. Thought I was already working on a pretty critical project last week, until I was re-assigned to doing "fire fighting" on an apparently even more critical one...
sublue wrote:I don't rate puzzles with a number scale, but put this one down as disturbingly easy.
Afmob wrote:I guess I missed something since I used a chain to crack it.
Like Afmob, I must be missing something, too. Managed to find 90 minutes or so to have a crack at this one, and promptly failed to make any real impression on it. I've run out of time now, so will have to put it on hold for the moment. :(

I now look forward to reading the other WTs (as soon as I have the time) and discovering which easy moves I missed!
Cheers,
Mike
Andrew
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Post by Andrew »

Mike wrote:Like Afmob, I must be missing something, too. Managed to find 90 minutes or so to have a crack at this one, and promptly failed to make any real impression on it. I've run out of time now, so will have to put it on hold for the moment. :(

I now look forward to reading the other WTs (as soon as I have the time) and discovering which easy moves I missed!
Hope you can find some of them below. :wink:

I took longer than I should have done because I initially made a silly mistake in step 27. However once I'd sorted that out and extended step 27 the rest of it came fairly smoothly.

I'll rate A89 as a moderate to hard 1.25. I don't think steps 25 and 26 require a higher rating.

Here is my walkthrough. I think the key steps are 25, 26, 27 and 33.

Prelims

a) R1C23 = {29/38/47/56}, no 1
b) R3C67 = {49/58/67}, no 1,2,3
c) R7C34 = {16/25/34}, no 7,8,9
d) R9C89 = {18/27/36/45}, no 9
e) 21(3) cage at R1C7 = {489/579/678}, no 1,2,3
f) 11(3) cage in N3 = {128/137/146/236/245}, no 9
g) R345C3 = {289/379/469/478/568}, no 1
h) 10(3) cage in N4 = {127/136/145/235}, no 8,9
i) R6C123 = {389/479/569/578}, no 1,2
j) R567C7 = {589/679}, 9 locked for C7, clean-up: no 4 in R3C6
k) 10(3) cage at R7C6 = {127/136/145/235}, no 8,9
l) 19(3) cage at R8C3 = {289/379/469/478/568}, no 1
m) 14(4) cage in N2 = {1238/1247/1256/1346/2345}, no 9

1. 9 in R1 locked in R1C123, locked for N1

2. 21(3) cage at R1C7 = {489/579/678}
2a. 9 of {489/579} must be in R2C6 -> no 4,5 in R2C6

3. 45 rule on N5 2 outies R37C5 = 8 = {17/26/35}, no 4,8,9
3a. 45 rule on N5 3 innies R456C5 = 19 = {289/379/469/478/568}, no 1

4. 45 rule on C12 2 outies R16C3 = 12 = {39/48/57}, no 2,6, clean-up: no 5,9 in R1C2

5. 45 rule on C89 2 outies R49C7 = 3 = {12}, locked for C7, clean-up: R9C8 = {78}
5a. Max R4C7 = 2 -> min R4C89 = 14, no 1,2,3,4

6. R8C7 = 3 (hidden single in C7)
[Alternatively 45 rule on N69 1 innie R8C7 = 3]
6a. R78C6 = 7 = {16/25}, no 4,7

7. 45 rule on N14 1 innie R2C3 = 1, clean-up: no 6 in R7C4
7a. R23C4 = 13 = {49/58/67}, no 2,3

8. 45 rule on N3 2 outies R23C6 = 17 = {89}, locked for C6 and N2, clean-up: R3C7 = {45}, no 4,5 in R23C4 (step 7a)
8a. Naked pair {67} in R23C4, locked for C4 and N2, clean-up: no 1,2 in R7C5 (step 2)

9. 45 rule on N2 1 remaining innie R3C5 = 1, R7C5 = 7 (step 3)
9a. R456C5 (step 3a) = {289/469/568}, no 3

10. Killer quad 2,3,4,5 in R1C23 and R1C456, locked for R1

11. 21(3) cage at R1C7 = {489/579/678}
11a. 4 of {489} must be in R2C7, 8 of {678} must be in R2C6 -> no 8 in R2C7

12. 4 in C7 locked in R23C7, locked for N3
12a. 1 in R1 locked in R1C89
12b. 11(3) cage in N3 = {128/137}, no 5,6
12c. 2,3 only in R2C9 -> R2C9 = {23}
12d. Killer pair 7,8 in R12C7 and 11(3) cage, locked for N3
[Alternatively 9 in N3 locked in 17(3) cage = {269/359}]
12e. 8 in N3 locked in R1C789, locked for R1, clean-up: no 3 in R1C23, no 4,9 in R6C3 (step 4)
12f. 3 in R1 locked in R1C456, locked for N2

13. 45 rule on N7 2 outies R78C4 = 13 = [49/58], clean-up: R7C3 = {23}
13a. 3 in N8 locked in R9C456, locked for R9

14. 45 rule on C1234 2 innies R19C4 = 5 = {23}/[41]

15. 45 rule on C6789 2 innies R19C6 = 9 = [36]/{45}
15a. Killer triple 4,5,6 in R7C4, R78C6 and R9C6, locked for N8

16. 6 in C5 locked in R456C5, locked for N5
16a. R456C5 = {469/568}, no 2

17. 7 in C6 locked in R456C6 = {147/237}, no 5

18. 45 rule on N4 1 outie R3C3 = 1 innie R4C2 + 4, R3C3 = {5678}, R4C2 = {1234}

19. 45 rule on N6 1 outie R7C7 = 1 innie R6C8 + 6, R7C7 = {89}, R6C8 = {23}

20. R789C9 = {149/158/248/257} (cannot be {167} which clashes with R9C78), no 6
20a. Killer pair 1,2 in R789C9 and R9C7, locked for N9
20b. R12C9 cannot be [12] which clashes with R789C9 -> no 8 in R1C8
20c. Killer triple 7,8,9 in R7C7, R789C9 and R9C8, locked for N9

21. R678C8 = {256/346}, 6 locked for C8

22. 4 in N6 locked in 13(3) cage = 4{18/27/36}, no 5,9

23. 45 rule on N7 3 innies R789C3 = 13 = {238/247/256/346}, no 9

24. 45 rule on N3 3 innies R123C7 = 17 = {458/467}
24a. {458} must be [845] (cannot be [854] which clashes with 21(3) cage), no 5 in R2C7

25. 15(3) cage in N7 = {159/168/258/348} (cannot be {249/267/357} which clash with R789C3, cannot be {456} which clashes with R7C4 + R7C8), no 7
25a. 3 in N7 must be in R7C123 -> either 15(3) cage must contain 3 or R789C3 = 3{28/46} -> 15(3) cage cannot be {168}
25b. 15(3) cage = {159/258/348}, no 6

26. 17(3) cage in N7 = {179/269/278/467} (cannot be {458} which clashes with 15(3) cage), no 5
26a. 1 in N7 must be in 15(3) cage or 17(3) cage, if 17(3) not {179} => 15(3) = {159} -> 17(3) cannot be {269}
26b. 17(3) cage = {179/278/467}, 7 locked for N7
26c. 9 of {179} must be in R9C12 (cannot be 9{17} which clashes with R9C78), no 9 in R8C1
26d. R789C3 (step 23) = {238/256/346}

27. 45 rule on N4 3 innies R4C23 + R5C3 = 15 = {249/348} (cannot be {159/267/357} which clash with R345C3, cannot be {168/258/456} because R345C3 = {568} clashes with R789C3), no 1,5,6,7, clean-up: no 5 in R3C3 (step 18)
27a. R345C3 = {289/469/478} (cannot be {379} which clashes with R4C23 + R5C3), no 3
27b. 4 locked in R4C23 + R5C3, locked for N4

28. 1 in N4 locked in 10(3) cage = {127/136}, no 5

29. 5 in N4 locked in R6C123, locked for R6
29a. R6C123 = {569/578}, no 3
[Alternatively this follows from hidden killer pair 6,7 in 10(3) cage and R6C123]

30. R567C7 = {589/679}
30a. 5 of {589} must be in R5C7 -> no 8 in R5C7
30b. 5 of {589} must be in R5C7 and 9 of {679} must be in R7C7 -> no 9 in R5C7

31. R7C3 = 3 (hidden single in C3), R7C4 = 4, R8C4 = 9 (step 13), clean-up: no 5 in R1C6 (step 15), no 1 in R9C4 (step 14)
31a. Naked pair {23} in R19C4, locked for C4
31b. R8C4 = 9 -> R89C3 = {28/46}, no 5

32. Naked triple {158} in R456C4, locked for N4
32a. Naked triple {469} in R456C5, locked for C5 and N5
32b. Naked triple {237} in R456C6, locked for C6 -> R1C6 = 4, R9C6 = 5 (step 15), clean-up: no 7 in R1C23

33. R4C23 + R5C3 (step 27) = {249} (cannot be {348} which clashes with R89C3), locked for N4, clean-up: no 7 in R3C3 (step 18), no 7 in 10(3) cage (step 28), no 6 in R6C123 (step 29a)
33a. 9 locked in R45C3, locked for C3 -> R1C3 = 5, R1C2 = 6, R3C3 = 8, R4C2 = 4 (step 18), R6C3 = 7, R3C6 = 9, R3C7 = 4, R2C6 = 8, R12C7 = [76], R1C1 = 9, R1C89 = [18], R2C9 = 2 (step 12b), R2C5 = 5, R5C7 = 5, R23C4 = [76], R2C12 = [43], R2C8 = 9, R3C12 = [27] (cage sums), R5C2 = 1, R56C4 = [81], R4C4 = 5, clean-up: no 2 in R89C3 (step 31b)

34. Naked pair {58} in R6C12, locked for R6 -> R67C7 = [98], R6C8 = 2 (step 19), R6C6 = 3, R4C7 = 1, R9C78 = [27], R9C4 = 3, R9C5 = 8, R8C5 = 2, R9C2 = 9, R1C45 = [23], clean-up: no 7 in R5C89 (step 22), no 4 in R8C8 (step 21)

35. Naked pair {56} in R78C8, locked for C8 and N9

and the rest is naked singles
Last edited by Andrew on Fri Feb 15, 2008 2:54 am, edited 1 time in total.
HATMAN
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Post by HATMAN »

I remember starting with heavy work on:
N3: outies r23c6 = {89} combos on innies r123c7 = {67}4 | {48}5 = 4..
N3: -> 17/3 = 9..-> 674,935,128 | 485,917,236 | 485,926,137
innies on C7 -> r489 = {123}
And then working on N6 and N9
Save a GRUE: eat a brass lantern
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