SudokuSolver Forum

A forum for Sudoku enthusiasts to share puzzles, techniques and software
It is currently Tue Mar 19, 2024 3:33 am

All times are UTC




Post new topic Reply to topic  [ 4 posts ] 
Author Message
 Post subject: Assassin 342
PostPosted: Sun Feb 19, 2017 11:34 am 
Offline
Grand Master
Grand Master

Joined: Wed Apr 30, 2008 9:45 pm
Posts: 692
Location: Saudi Arabia
Assassin 342

I could not get this at the level I wanted (bouncing from 1.0 to 2+). SS gives it 1.55 and JS uses five fishes.

Image

JSCode:
3x3::k:2571:2571:4621:4621:4621:4622:4622:4105:4105:2571:6163:5634:4870:4870:4870:5121:4622:4105:6163:5634:5634:5634:4870:5121:5121:5121:3089:6163:4613:5634:22:4629:23:5121:5127:3089:4372:4613:4613:4629:4629:4629:5127:5127:3089:4372:4613:5635:24:4629:25:4612:5127:5650:4372:5635:5635:5635:4360:4612:4612:4612:5650:3084:6159:5635:4360:4360:4360:4612:5650:2826:3084:3084:6159:6159:5136:5136:5136:2826:2826:

Solution:
165492783
384176295
927358164
756819342
439527816
812634579
573941628
691283457
248765931


Top
 Profile  
Reply with quote  
 Post subject: Re: Assassin 342
PostPosted: Sat Feb 25, 2017 12:50 am 
Offline
Addict
Addict

Joined: Mon Apr 28, 2008 10:58 pm
Posts: 47
Location: Victoria, B.C., Canada
Finally able to do one of your assassins HATMAN :). Here is how I started.
The start:
Outies of each of the outside rows and columns yield a mass of stuff including 2 9's and an 8. Also, r8c9 reduces to {78}. If r8c9 = 8 then the 11/2 cage in n9 is (128) and the {12} of the 18/5 cage lies outside n9. That leaves {348|357|456} for inside n9 which doesn't work. So r8c9 = 7.

After that start I thought the puzzle was cracked. But when I tried to repeat the solution I got stuck. Eventually the following ugly move unlocked it.
Ugly move:
The 18/5 cage at the bottom right is either {12348} or {12456}. I tried {12348} and eventually reached a contradiction. So the cage is {12456}

After that the puzzle fell apart - but not a very satisfying solution :(.

Many thanx HATMAN - Cheers - Frank


Top
 Profile  
Reply with quote  
 Post subject: Re: Assassin 342
PostPosted: Sat Mar 04, 2017 9:49 pm 
Offline
Grand Master
Grand Master

Joined: Tue Jun 16, 2009 9:31 pm
Posts: 280
Location: California, out of London
I followed the same path as Frank described. Thanks for a fine puzzle HATMAN. Here is my start...
Assassin 342 WT:
1. Min r9c1289 = +10 -> Max r9c34 = +15
-> 24(3)r8c2 = [9{78}]
-> 20(3)r9 = {569}
Also 9 in 22(3)r6c9 in r67c9.

2. Max r9c2 = 4
-> Outies c1 -> Min r12c2 = +14(2) -> must include an 8
Since Max r1c2 = 7 -> r2c2 = 8
-> r34c1 = {79}
Also -> r19c2 from [64] or [73]
-> 10(3)n1 = {127} or {136} with (7 or 6) in r1c2
-> 1 in r9 in r9c89

3. Max r2c1 = 3 -> (Outies r1) Min r2c89 = +14(2)
-> Since 8 already in r2 and 9 already in c9 -> r2c8 = 9

4! 12(3)n7 only from [624] or [5{34}]
-> 11(3)n9 from [7{31}] or [8{12}]
-> 4 in n9 only in 18(5)
-> 18(5) from {12348} or {12456}
3 in n9 either in 18(5) or in 11(3)
But the former makes 18(5) = {12348} which leaves no solution for 11(3)n9
-> 11(3)n9 = [7{13}]
-> 12(3)n7 = [624]
-> r1c2 = 6 and r12c1 = {13}
-> 17(3)c1 = {458} with 4 in r56c1
Also 22(3)r6c9 = {589} with 9 in r67c9.

5. Remaining outies r1 -> r2c19 = +8(2) = [35]
-> r1c1 = 1
Also -> r8c8 = 5, r67c9 = {89}
-> Remaining Outies c9 -> r19c8 = +11(2) = [83]
-> r1c9 = 3
-> 12(3)c9 = {246}

6! Whichever two of (246) are in r45c9 must go in c8 in r37c8.
-> r456c8 = {17(2|4|6)}
-> 20(4)n6 = {1478} with r5c7 = 8 and r456c8 = {147}
-> r37c8 = {26}, 12(3)c9 = [4{26}]
-> r67c9 = [98]
-> r46c7 = {35}
Also 9 in n5 in r4c46
-> r34c1 = [97]
Also 20(3)r9 = [{56}9]
=> 18(5)r6c7 = [51{246}]
-> Remaining innies n8 = r79c4 = [97]
etc.


Top
 Profile  
Reply with quote  
 Post subject: Re: Assassin 342
PostPosted: Mon Mar 13, 2017 11:07 pm 
Offline
Grand Master
Grand Master

Joined: Wed Apr 23, 2008 6:04 pm
Posts: 1893
Location: Lethbridge, Alberta, Canada
So did I, to some extent. There's clearly that path built into this Assassin.

I saw various steps in different ways, I particularly liked the way wellbeback saw the steps for the early placements. Then I found it heavier going before I made my breakthrough, not helped by only spotting steps 3f and 3g after I'd done step 8.

Here is my walkthrough for Assassin 342:
Prelims

a) 10(3) cage at R1C1 = {127/136/145/235}, no 8,9
b) 24(3) cage at R2C2 = {789}
c) 22(3) cage at R6C9 = {589/679}
d) 24(3) cage at R8C2 = {789}
e) 11(3) cage at R8C9 = {128/137/146/236/245}, no 9
f) 20(3) cage at R9C5 = {389/479/569/578}, no 1,2
g) 18(5) cage at R4C5 = {12348/12357/12456}, no 9
h) 18(5) cage at R6C7 = {12348/12357/12456}, no 9

Steps resulting from Prelims
1a. 24(3) cage at R2C2 = {789}, CPE no 7 in R12C1
1b. 24(3) cage at R8C2 = {789}, CPE no 7,8,9 in R9C12
1c. 18(5) cage at R4C5 = {12348/12357/12456}, 1,2 locked for N5

2. 20(3) cage at R9C5 = {569} (only possible combination, cannot be {389/479/578} which clash with 24(3) cage at R8C2, ALS block), locked for R9
2a. R9C34 = {78}, locked for R9 and 24(3) cage -> R8C2 = 9
2b. 24(3) cage at R2C2 = {789}, 9 locked for C1
2c. 22(3) cage at R6C9 = {589/679}, 9 locked for C9
2d. 45 rule on R9 2 remaining outies R8C19 = 13 = {58/67}
2e. 17(3) cage at R5C1 = {368/458/467} (cannot be {278} which clashes with 24(3) cage at R2C2, ALS block), no 1,2
2f. Killer triple 7,8,9 in 24(3) cage and 17(3) cage, locked for C1, clean-up: no 5,6 in R8C9
2g. Killer pair 5,6 in 17(3) cage and R8C1, locked for C1
2h. 10(3) cage at R1C1 must contain one of 5,6,7 -> R1C2 = {567}

3. 45 rule on C1 3 outies R129C2 = 18 = {378/468} (cannot be {567} because no 5,6,7 in R9C2) -> R2C2 = 8, R19C2 = [63/74]
3a. R34C1 = {79}, locked for C1
3b. 10(3) cage at R1C1 = {127/136}, no 4, 1 locked for C1 and N1
3c. 12(3) cage at R8C1 = {246/345}, no 1, 4 locked for R9 and N7
3d. 1 in R9 only in R9C89, locked for N9
3e. 1 in N7 only in R7C23 + R8C3, locked for 22(5) cage at R6C3, no 1 in R6C3 + R7C4
3f. 4 in N9 only in R7C78 + R8C8, locked for 18(5) cage at R6C7, no 4 in R6C7 + R7C6
3g. 18(5) cage = {12348/12456}, no 7
3h. 7 in N9 only in R7C9 + R8C89, CPE no 7 in R6C9

4. 45 rule on R1 3 outies R2C189 = 17 = {179/269/359} (cannot be {467} because R2C1 only contains 1,2,3) -> R2C8 = 9
4a. R2C19 = [17/26/35]

5. 45 rule on C9 3 outies R189C8 = 16 = {178/268/358/367} (cannot be {457} because R9C8 only contains 1,2,3), no 4
5a. R9C8 = {123} -> no 1,2,3 in R1C8
5b. 16(3) cage at R1C8 = {178/268/358/367/457} -> R1C9 = {1234}

6. 11(3) cage at R8C9 = 8{12}/7{13}
6a. 12(3) cage at R3C9 = {147/156/237/246/345} (cannot be {138} which clashes with 11(3) cage), no 8
6b. 8 in C9 only in 22(3) cage at R6C9 and R8C9, CPE no 8 in R8C8
6c. R189C8 (step 5) = [763/853/862/871] (cannot be [673] which clashes with 11(3) cage), no 5,6 in R1C8
6d. 22(3) cage at R6C9 = {589/679}
6e. 5 of {589} must be in R8C8 -> no 5 in R67C9
6f. R8C19 (step 2d) = {58/67}, R8C8 = {567} -> combined half-cage R8C189 = [5{67}8/658], 5 locked for R8

7. 9 in R1 only in 18(3) cage at R1C3
7a. 5 in R1 only in 18(3) cage at R1C3 = {459} or 18(3) cage at R1C6 = {459}, 4 locked for R1 (locking cages)
7b. 4 in C9 only in 12(3) cage at R3C9 (step 6a) = {147/246/345}
7c. 5 in C9 only in R2C9 and 12(3) cage
7d. 16(3) cage at R1C8 (step 5b) = [817/826/835] (cannot be [736] which clashes with 12(3) cage = {345}, only other position for 5 in C9) -> R1C8 = 8
7e. R12C9 = 8 -> 5 in C9 only in R12C8 = [35] or 12(3) cage = {345}, 3 locked for C9 (locking cages)
7f. 18(3) cage at R1C3 = {279/369/459}, no 1
7g. 18(3) cage at R1C6 = {279/369/459}, no 1

8. 45 rule on R12 2 remaining innies R2C37 = 1 outie R3C5 + 1, min R2C37 = 3 -> min R3C5 = 2
8a. 45 rule on C12 2 remaining innies R37C2= 1 outie R5C3, min R37C2 = 3 -> min R5C7 = 3
8b. 45 rule on C89 2 remaining innies R37C8 = 1 outie R5C7, min R37C8 = 3 -> min R5C7 = 3

9. 45 rule on N9 3(2+1) outies R6C79 + R7C6 = 1 innie R9C7 + 6
9a. R9C7 = {56}, min R6C9 = 6 => max R6C7 + R7C6 = 6
or R9C7 = 9, R6C9 = 9 (hidden single in C9) => R6C7 + R7C6 = 6
-> no 6,8 in R6C7 + R7C6
9b. 18(5) cage (step 3g) = {12348/12456}
9c. R8C19 (step 2d) = [58/67] -> R8C189 = [578/657] (cannot be [568] which clashes with 18(5) cage) -> R8C8 = {57}, 7 locked for R8 and N9
9d. R1C8 = 8 -> R89C8 (step 5) = 8 = [53/71]
9e. Hidden killer pair 2,3 in R7C78 + R8C7 and R9C89 for N9, R7C78 + R8C7 must contain one of 2,3, also contain 4 and one of 6,8 -> no 5 in R7C78
9f. 1,5 of {12456} must be in R6C7 + R7C6, 1,3 of {12348} must be in R6C7 + R7C8 (R7C78 + R8C7 cannot be {348} which clashes with 11(3) cage at R8C9) -> no 2 in R6C7 + R7C6

10. 18(5) cage (step 3g) = {12348/12456}, 2 locked for N9 -> R9C89 = [31], R8C9 = 7 (cage sum), R8C8 = 5, R8C1 = 6, R9C12 = [24]
10a. R1C1 = 1 (hidden single in R1), R2C1 = 3 -> R1C2 = 6 (cage sum)
10b. 4 in C1 only in R56C1, locked for N4
10c. 3 in N7 only in R7C23 + R8C3, locked for 22(5) cage at R6C3, no 3 in R6C3 + R7C4
10d. 18(3) cage at R1C3 = {279/459}, no 3
10e. 18(3) cage at R1C5 = {279/459}, no 3
10f. R1C9 = 3 (hidden single in R1) -> R2C9 = 5 (cage sum), clean-up: no 4 in R1C6
10g. Naked triple {246} in 12(3) cage at R3C9, locked for C9
10h. 1 in N3 only in R2C7 + R3C78, locked for 20(5) cage at R2C7, no 1 in R3C6 + R4C7

11. 20(4) cage at R4C8 = {1478} (only possible combination, cannot be {1289/1379/1568/2369/2378/2459/3458} because 3,5,8,9 only in R5C7), cannot be {1469/2468/2567/3467} which clash with 12(3) cage at R3C9, ALS block) -> R5C7 = 8, R456C8 = {147}, locked for C8 and N6
[Cracked, the rest is straightforward; I was surprised that this cage can only have one combination when it was the first time I looked at it.]
11a. R67C9 = [98], 17(3) cage at R5C1 = [485]
11b. R7C78 + R8C7 = {246}, locked for N7, 4 also locked for C7, R9C7 = 9
11c. R7C78 + R8C7 = {246} -> R6C7 + R7C6 = 6 = [51]
11d. Naked pair {56} in R9C56, locked for N8
11e. 18(3) cage at R1C6 = {279}, 2,7 locked for R1
11f. Naked pair {26} in R45C9, locked for C9 and N6 -> R3C9 = 4, R4C7 = 3
11g. Naked pair {37} in R7C23, locked for R7, N7 and 22(5) cage at R6C3 -> R9C34 = [87], R8C3 = 1
11h. R7C23 = {37}, R8C3 = 1 -> R6C3 + R7C4 = 11 = [29]

12. R3C2 = 2 (hidden single in C2), R37C8 = [62], R78C7 = [64], R7C5 = 4
12a. R3C8 = 6, R4C7 = 3, R23C7 contains 1 -> remaining two values in 20(5) cage at R2C7 must total 10 -> R2C7 = 2, R3C6 = 8, R3C7 = 1, R1C67 = [27]

13. R5C3 = 9 (hidden single in R5) -> R456C2 = 9 = {135}, locked for C2 and N4, R34C1 = [97]
13a. R3C2 = 2, R4C3 = 6 -> R2C3 + R3C34 = 14 = [473]

14. 18(5) cage at R4C5 = {12357} (only remaining combination), locked for N5

and the rest is naked singles.

Rating Comment:
I'll rate my walkthrough for A342 at 1.5. wellbeback's step 4 would get this puzzle a lower rating.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 4 posts ] 

All times are UTC


Who is online

Users browsing this forum: No registered users and 10 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group