Assassin 85

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CathyW
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Assassin 85

Post by CathyW »

Hello all and a belated Happy New Year! :D

I see no-one has yet posted about this week's assassin and I'm not surprised. I have 3 placements and am totally stuck. Tried it again using JS which cannot solve it!

(I'm unlikely to be posting any WTs any time soon - especially when the puzzles are as hard as this week's but will still be dropping in when possible. )
Ruud
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Post by Ruud »

Shame on me :oops:

I verified this puzzle with Richard's solver and it gave a rating of 1.38, which is usually on the spot for an Assassin. The phrase "******* Puzzle Not completed. *******" just scrolled out of sight in the solver log.

The Assassin has been replaced with a more suitable puzzle.

For those who still want to have a go at the original:

3x3::k:5376:5376:4098:4098:1284:2821:2821:2567:2567:5376:4618:4618:4618:1284:6158:6158:6158:2567:2578:4618:3348:3348:5654:4375:4375:6158:3354:2578:4618:3348:5654:5654:5654:4375:6158:3354:1828:1828:8486:8486:8486:8486:8486:1323:1323:2605:7470:4399:4144:4144:4144:2611:5940:3125:2605:7470:4399:4399:4144:2611:2611:5940:3125:3903:7470:7470:7470:3395:5940:5940:5940:4423:3903:3903:2378:2378:3395:2381:2381:4423:4423:

My apologies for the distress this puzzle caused.

Ruud
mhparker
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Post by mhparker »

Ruud wrote:I verified this puzzle with Richard's solver and it gave a rating of 1.38, which is usually on the spot for an Assassin. The phrase "******* Puzzle Not completed. *******" just scrolled out of sight in the solver log.
Yes, I've also (almost) fallen into this trap myself. I was going to mention it to Richard, because it's a bit misleading for SS to display a score for a puzzle it cannot complete. It's also a bit annoying to have to scroll back to check for the "******* Puzzle Not completed. *******" each time. (BTW, Richard, whilst on the subject of enhancement requests, it would also be nice to have a shortcut key combination for the "Score" menu item...).
Cheers,
Mike
Andrew
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Post by Andrew »

I also made similar progress to Cathy on the original puzzle. An easy start with 3 placements and a lot of simplification in the top third of the puzzle. Then apart from 4 innies for C6789 R456C6 + R5C7 = 29, min R456C6 = 20, min R5C7 = 5, I hadn't been able to make any further progress.

I'll have a go at the modified puzzle with different cage totals as soon as I have time.

Maybe the original puzzle should be put in the Unsolvables with a diagram?
Last edited by Andrew on Sat Jan 12, 2008 12:41 am, edited 1 time in total.
herschko
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Post by herschko »

Shame on me Embarassed

I verified this puzzle with Richard's solver and it gave a rating of 1.38, which is usually on the spot for an Assassin. The phrase "******* Puzzle Not completed. *******" just scrolled out of sight in the solver log.
*Now* you tell me. I was wondering I had to resort to massive guessing to get this done. I thought I had lost my touch.
-SJH
rcbroughton
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Post by rcbroughton »

mhparker wrote:
Ruud wrote:I verified this puzzle with Richard's solver and it gave a rating of 1.38, which is usually on the spot for an Assassin. The phrase "******* Puzzle Not completed. *******" just scrolled out of sight in the solver log.
Yes, I've also (almost) fallen into this trap myself. I was going to mention it to Richard, because it's a bit misleading for SS to display a score for a puzzle it cannot complete. It's also a bit annoying to have to scroll back to check for the "******* Puzzle Not completed. *******" each time. (BTW, Richard, whilst on the subject of enhancement requests, it would also be nice to have a shortcut key combination for the "Score" menu item...).
Oops! Sorry for that - I'd actually planned to take out the score completely if it didn't solve - just got distracted on other things like building in Rotation/Flip/Mirror functions and trying to get the sollving path to be relatively consistent on rotated puzzles.
No problem putting in a shortcut - I also want to make sure that when Scoring that the "official" routines order is automatically selected - there can be a significant variation to the solving path based on what the routine order is.
Afmob
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Post by Afmob »

This killer had some nice Killer quads you could use to speed things up.

I haven't given up on the V1 version yet and I try to resist using a hypothetical but seems like I'm coming to a dead end. By the way, SudokuSolver rated V1 with 4.5 (A74 Brick Wall 3.63, A60 RP 4.38) so using our rating system it's probably a 2.0-2.5.

A85 V0 (correct version) Walkthrough:

1. R1234
a) 7(3) = {124} locked for N1
b) 9(2) @ N1: R1C4 <> 5,7,8
c) Outies R12 = 13(2+2): R34C8 <> 9 because R34C2 >= 4
d) Outies R12 = 13(2+2): R4C2 <> 8,9 because R3C2 >= 3
e) Naked quad (6789) locked in R3C1679 for R3
f) Naked pair (35) locked in R3C23 for R3+N1
g) 9(2) @ N1: R1C4 <> 4,6
h) 11(3) = {137/236/245} because R3C3 = (35) -> R4C3 <> 3,5,8

2. N3
a) Killer quad (6789) locked in 16(3) + R1C7+R3C79
b) 16(3) <> 1,6 because three of (6789) must be in R1C7+R3C79
c) 1 locked in 22(5) -> R2C6+R4C8 <> 1
d) Outies = 46(3+3) -> R123C6 and R4C789 <= 24 and >= 22
-> no 2,3,4 and 9 locked for C6+N2, 9 locked for R4+N6

3. R1234
a) 13(4) = 1{237/246/345} -> 1 locked between C5+N5 -> R56C5 <> 1
b) 5,6,7,8,9 locked in R4C1789 + 13(3) for R4
c) 11(3) = {245} -> R3C3 = 5
d) R3C2 = 3
e) Killer quad (1234) locked in 9(2) @ R1C5 + R13C4+R3C5 for N2
f) 15(2) @ N1: R3C1 <> 6
g) 3 locked in 13(4) @ R4 for N5 -> 13(4) <> 6

4. C9
a) 4(2) = {13} locked for C9
b) 6(2): R5C8 <> 5

5. R6789
a) Outies R89 = 29(2+2) <> 1,2
b) Outies R89 = 29(2+2): R7C8 <> 3 because R67C8 must be >= 12
c) 13(2): R9C4 <> 8

6. R123
a) Innies R1 = 21(5) = {12459/13458/23457} <> 6 because 4,5 locked there
b) 9(2) @ R1C5: R2C5 <> 3
c) Outies R1 = 11(3) <> 7,9
d) 9(2) @ R1C5: R1C5 <> 2
e) 3 locked in R2C78 @ 22(5) for N3
f) 16(3) = 5{29/47} -> 5 locked for N3
g) Killer pair (79) locked in 15(2) + 16(3) for R1
h) 9(2) @ R1C3 = [63/81]
i) Killer pair (68) locked in 15(2) + 9(2) for R1
j) 9(2) @ R1C5: R2C5 <> 1,2
k) 2 locked in R3C45 for R3

7. R123 !
a) 25(5) = 3{1579/1678/2569/2578/4567} because (124) only possible @ R4C2
b) 25(5): R2C4 <> 7 because 5 only possible there and R1C3 = (68) blocks {13678}
c) 7 locked in R12C6 for C6
d) ! Outies R12 = 10(2+1) <> 6 because R3C8+R4C2 <> 3 and Outies must have 1
e) ! 22(5): R2C6 <> 7 because 6,9 only possible there
f) Hidden Single: R1C6 = 7 @ N2 -> R1C7 = 8
g) 9(2) @ R1C3 = {36} -> R1C3 = 6, R1C4 = 3
h) Hidden Single: R3C9 = 7 @ N3 -> R4C9 = 8
i) 23(3) = {689} -> R3C6 = 8, {69} locked for C7
j) 9(2) = {45} locked for C5+N2
k) 25(5) = {13678} -> R2C4 = 6, R4C2 = 1

8. N3
a) 16(3) = {259} locked for N3
b) 22(5) = {13459} -> R2C6 = 9, R4C8 = 5

9. R456
a) 6(2) = {24} locked for R5+N6
b) 13(2) <> 9
c) 13(4) = {1237} -> 7 locked for R4+N5; R6C5 <> 2
d) R3C1 = 9, R4C1 = 6
e) 13(2) = {58} locked for R5+N4
f) 8(2) = [35/71]

10. C789
a) Outies C9 = 12(3) = 2{19/46} -> 2 locked for C8; R9C8 = (16)
b) Hidden Single: R6C8 = 6 @ N6
c) 16(3) @ N9 = {169} -> R9C8 = 1, {69} locked for C9+N9

11. R789
a) 13(2) <> 7
b) 7(2) <> 6
c) Killer pair (45) locked in 7(2) + 13(2) for R9
d) Hidden pair (78) locked in R78C8 for C8 -> no other candidates -> 7 locked for N9
e) 27(5) = 678{15/24} -> R8C6 <> 3,5; R8C7 <> 3
f) Outies R9 = 17(3): R8C5 <> 2 because R8C1 <> 6,9 and R8C9 <> 7,8
g) 9(2): R8C5 <> 8, R9C5 <> 7
h) 7 locked in R9C12 for N7
i) 17(3) = 7{19/28/46}
j) Hidden Single: R6C1 = 3 @ C1 -> R7C1 = 5
k) 13(3) = {247} -> R6C7 = 7, {24} locked for R7

12. C123
a) R3C4 = 2, R4C3 = 4, R4C4 = 7, R6C2 = 9, R6C3 = 2
b) 12(3) = {129} -> {19} locked for R7
c) 30(5) = 689{25/34} -> 6 locked for N7
d) 17(3) = {278} locked for N7
e) 13(2) = {49} -> R9C3 = 9, R9C4 = 4

13. Rest is singles.

Rating: 1.25. I used a bit of combo analysis and Killer quads.
Last edited by Afmob on Mon Jan 14, 2008 6:34 am, edited 1 time in total.
Andrew
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Post by Andrew »

Wouldn't it be better to call the original version V2 and the puzzle now on the main Assassin page V1?

I've renamed my files that way. It makes more sense to me and also goes along with the original concept of V2s.
gary w
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Post by gary w »

I only got round to looking at this one today...oh dear !!!I'm glad it wasn't just me.I was at least able to show that r5c7=7/8/9 but apart from that nothing.I'm impressed that it was done even using hypotheticals altho' I haven't resorted to that myself yet.

Regards

Gary
Andrew
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Post by Andrew »

Only just finished, at very late bedtime, so haven't yet had time to check my walkthrough or go through Afmob's one.

Edit. I've now done that and corrected one typo in my walkthrough. Afmob's step 2d is a neat one! It's unusual to spot a step like that so early.

Here is my walkthrough for A85 (the modified one on the main Assassin page) which I rate at 1.25. It needed some killers and hidden killers plus a little combo analysis but less of that after I found step 3 and then reworked the steps from there.

Prelims

a) R1C34 = {18/27/36/45}, no 9
b) R12C5 = {18/27/36/45}, no 9
c) R1C67 = {69/78}
d) R34C1 = {69/78}
e) R34C9 = {69/78}
f) R5C12 = {49/58/67}, no 1,2,3
g) R5C89 = {15/24}
h) R67C1 = {17/26/35}, no 4,8,9
i) R67C9 = {13}, locked for C9, clean-up: no 5 in R5C8
j) R89C5 = {18/27/36/45}, no 9
k) R9C34 = {49/58/67}, no 1,2,3
l) R9C67 = {16/25/34}, no 7,8,9
m) 7(3) cage in N1 = {124}, locked for N1, clean-up: no 5,7,8 in R1C4
n) 11(3) cage at R3C3 = {128/137/146/236/245}, no 9
o) 23(3) cage at R3C7 = {689}
p) 13(4) cage at R3C5 = {1237/1246/1345}, no 8,9, CPE no 1 in R56C5

1. Killer quad 6,7,8,9 in R3C1, R3C67 and R3C9, locked for R3

2. Naked pair {35} in R3C23, locked for R3 and N1, clean-up: no 4,6 in R1C4

3. Killer single 6 in R1C3 and R1C67, locked for R1, clean-up: no 3 in R2C5

4. 11(3) cage at R3C3 = {137/236/245} (cannot be {128/146} because R3C3 only contains 3,5), no 8
4a. 6,7 of {137/236} must be in R4C3 -> no 1,3 in R4C3
4b. 5 of {245} must be in R3C3 -> no 5 in R4C3

5. Killer quad 1,2,3,4 in R1C4, R12C5 and R3C45, locked for N2

6. 45 rule on R1 3 outies R2C159 = 11 = {128/146/245}, no 7,9, clean-up: no 2 in R1C5

7. 25(5) cage at R2C2, min R2C234 + R3C2 = 21 -> max R4C2 = 4
7a. Only valid combinations with R2C23 = {6789}, R2C4 = {56789} and R3C2 = {35} are {13579/13678/23569/23578/34567}
7b. 1,2,4 only in R4C2 -> R4C2 = {124}
7c. 3 only in R3C2 -> R3C2 = 3, R3C3 = 5, clean-up: no 8 in R9C4
7d. 5 of {13579/23569} must be in R2C4 -> no 9 in R2C4
7e. R3C4 + R4C3 = {24} (step 4), CPE no 2,4 in R4C4

8. 9 in N2 locked in R123C6, locked for C6

9. 45 rule on R12 4 outies R34C2 + R34C8 = 13, R34C2 = 4,5,7 -> R34C8 = 6,8,9 = [15/24/42/17/26/18/27/45], no 1,3,9 in R4C8

10. 7 in R3 locked in R3C19 -> 8 in R4 locked in R4C19 (because of 15(2) cages), locked for R4
10a. 8 in 23(3) cage at R3C6 locked in R3C67, locked for R3, clean-up: no 7 in R4C19
10b. Naked triple {689} in R4C179, locked for R4

11. 13(4) cage at R3C5 = {1237/1345}, 3 locked in R4C456, locked for N5
11a. Hidden killer pair 5,7 in R4C456 and R4C8 -> R4C8 = {57}

12. Hidden killer quint 5,6,7,8,9 in R2C159, R2C234 and R2C678, R2C159 contains one of 5,6,8 (step 6), R2C234 contains three of 5,6,7,8,9 -> R2C678 must contain one of 5,6,7,8,9 which must be in R2C6 -> no 5,6,7,8,9 in R2C78
12a. 22(5) cage at R2C6 = {12379/12478/13459/23458/23467} (cannot be {12469/13468} because R4C8 only contains 5,7, cannot be {12568/13567} because of step 12)
12b. 5,7 must be in R4C8 -> no 5,7 in R2C6

13. 5 in N3 locked in 16(3) cage = 5{29/38/47}, no 1,6
13a. 3 of {358} must be in R1C8 -> no 8 in R1C8

14. 1 in N3 locked in R2C78 + R3C8
14a. 3 in R2 locked in R2C78
14b. -> 22(5) cage at R2C6 (step 12a) = {12379/13459} -> R2C6 = 9, clean-up: no 6 in R1C7

15. 9 in 23(3) cage locked in R34C7, locked for C7, clean-up: no 6 in R1C6

16. Naked pair {78} in R1C67, locked for R1 -> R1C34 = [63], clean-up: no 1,2,6 in R2C5, no 4 in R1C89, no 4,8 in R2C9 (both step 13), no 9 in R4C1, no 7 in R9C4

17. Naked triple {259} in 16(3) cage in N3, locked for N3, clean-up: no 6 in R4C9

18. Naked pair {68} in R3C67, locked for R3 -> R3C9 = 7, R3C1 = 9, R4C1 = 6, R4C7 = 9, R4C9 = 8, R1C67 = [78], R3C67 = [86], clean-up: no 1 in R1C5, no 7 in R5C1, no 4,7 in R5C2, no 2 in R67C1, no 1 in R9C6

19. Naked pair {45} in R12C5, locked for C5 and N2 -> R2C4 = 6, R3C45 = [21], R3C8 = 4, R4C3 = 4, clean-up: no 9 in R5C2, no 2 in R5C9, no 8 in R89C5, no 7 in R9C3, no 9 in R9C4

20. R4C2 = 1 (hidden single in R4 or cage sum), R4C8 = 5 (cage sum), R4C4 = 7, R1C1 = 1 (hidden single in R1), clean-up: no 7 in R67C1, no 1 in R5C8 -> R5C89 = [24], R1C8 = 9

21. Naked pair {23} in R4C56, locked for N5

22. Naked pair {25} in R12C9, locked for C9
22a. Naked pair {69} in R89C9, locked for N9, R9C8 = 1 (cage sum), R2C78 = [13], R67C9 = [13], R67C1 = [35], R5C12 = [85], R56C7 = [37], R6C8 = 6, clean-up: no 4,6 in R9C6

23. R5C3 = 7 (hidden single in R5), R2C23 = [78], R9C3 = 9, R9C4 = 4, R89C9 = [96], R6C23 = [92], R6C456 = [584], R78C3 = [13], clean-up: no 3 in R9C6

24. R7C4 = 9 (cage sum)

and the rest is naked singles and a cage sum
Last edited by Andrew on Mon Feb 22, 2010 10:34 pm, edited 1 time in total.
gary w
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Post by gary w »

Yes,the 2nd version was just a bit easier than the 1st !!



Combining the outies of N3 (46,3+3) with the 15(2) cages r34c19 and the 23(3) cage r3c67r4c7 the latter giving a complex x-wing on 689 -> r4c8=5 or 7.
But using this together with the 15(2) cage at r1c67 and cages in N3 you find that the only possibilities are as follows;r1c67=78,r2c6=9,r3c6=8,r3c79=67,r4c789=958.
In N1 r3c23={35}.Thus the 13(4) cage N2/5 <> 5 or 6 so = {1237}
Thus 11(3) cage N1/2/4={245} -> r3c3=5.

Pretty easy now.



I'ld go along with a1.25 rating.

Regards

Gary
mhparker
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Post by mhparker »

Hi guys,

With A86 just round the corner, I think I can avoid using TT now...

I just wanted to pick up on a term Andrew used in his WT, namely Killer Single:
Andrew wrote:3. Killer single 6 in R1C3 and R1C67, locked for R1, clean-up: no 3 in R2C5
Before I read this, I had never heard of this terminology. Normally, I would write out the logic in verbose form. For example (see candidate diagram below):
3. Either 15(2) at R1C6 = {69}, OR...
3a. ... = {78} -> R1C3 = 6
3b. -> 6 in R1 locked in R1C367 -> not elsewhere in R1
3c. cleanup: no 3 in R2C5
Others would write something like:
3. 15(2)n23 and R1C3 together lock 6 for R1...
So the terminology used by Andrew seemed to be wrong. Furthermore, JSudoku uses the term "Complex hidden single" (the equivalent in JSudoku nomenclature to "Killer hidden single") only for the situation where a single cage is known to contain a particular digit and there's only one candidate position remaining for it).

...to be continued...Unfortunately, there were some errors in my original post, so I had to delete my previous analysis :(
Cheers,
Mike
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