SudokuSolver Forum

A forum for Sudoku enthusiasts to share puzzles, techniques and software
It is currently Thu Mar 28, 2024 9:31 am

All times are UTC




Post new topic Reply to topic  [ 4 posts ] 
Author Message
 Post subject: Assassin 359
PostPosted: Thu Sep 20, 2018 7:57 am 
Offline
Grand Master
Grand Master

Joined: Wed Apr 16, 2008 1:16 am
Posts: 1040
Location: Sydney, Australia
Attachment:
a359.JPG
a359.JPG [ 67.1 KiB | Viewed 6122 times ]
Assassin 359
I can still make a symmetrical puzzle! SudokuSolver gives it 1.35. A fun one! Quite a long solution.
code:
3x3::k:3584:5633:5378:3093:3093:3093:4630:4630:4630:3584:5633:5378:5378:5378:3845:3845:3845:6406:3584:5633:5633:10247:3348:6406:6406:6406:6406:3584:3081:3081:10247:3348:3348:4874:4874:4874:3083:3083:5132:10247:10247:10247:4874:1805:1805:5132:5132:5132:2318:2318:10247:3855:3855:4368:6417:6417:6417:6417:2318:10247:5650:5650:4368:6417:4627:4627:4627:5636:5636:5636:5650:4368:2563:2563:2563:4360:4360:4360:5636:5650:4368:
solution:
Code:
+-------+-------+-------+
| 2 4 9 | 5 6 1 | 8 3 7 |
| 5 7 1 | 3 8 9 | 2 4 6 |
| 6 3 8 | 2 7 4 | 9 5 1 |
+-------+-------+-------+
| 1 5 7 | 8 4 2 | 3 6 9 |
| 4 8 6 | 9 3 7 | 1 2 5 |
| 9 2 3 | 6 1 5 | 7 8 4 |
+-------+-------+-------+
| 3 9 4 | 1 2 6 | 5 7 8 |
| 8 6 5 | 7 9 3 | 4 1 2 |
| 7 1 2 | 4 5 8 | 6 9 3 |
+-------+-------+-------+
Cheers
Ed


Top
 Profile  
Reply with quote  
 Post subject: Re: Assassin 359
PostPosted: Sun Sep 23, 2018 5:45 pm 
Offline
Grand Master
Grand Master

Joined: Tue Jun 16, 2009 9:31 pm
Posts: 280
Location: California, out of London
Hey - I'm caught up! :bouncy:
Is was either this or do my UK taxes. Easy choice :)

I found this quite straightforward but found it difficult to express concisely and clearly some of the steps. I'm sure there's a term for what Step 2 Line 2 does. Is this IOD?

Assassin 359 WT:
1. Innies n6 -> r6c9 = 4
-> Remaining Innies n9 -> r89c7 = +10(2)
-> r8c56 = +12(2)
Outies n7 -> r78c4 = +8(2)
-> Remaining Innies n8 -> r7c56 = +8(2)

2. Innies r9 -> r9c789 = +18(3)
Since r89c7 = +10(2) -> 8 not in r9c89
Since 8 in n8 in r8c56 or r9c456 -> 8 not in r9c7
-> 8 in r9 in r9c456
-> 4 also in r9c456
-> 17(3)n8 = {458}
-> H+12(2)r8c56 = {39}
-> r89c7 from [82] or [46]
Since 9 cannot go in 10(3)n7 -> r9c789 = [2{79}] or [6{39}]
-> 10(3)n7 = {136} or {127}

3. Max r8c23 = +15(2) -> Min r8c4 = 3
Since (345) already in n8 -> Outies n7 = r78c4 = +8(2) = [17] or [26]
-> Since (39) and one of (48) already in r8 -> 18(3)r8c2 = [{56}7] or [{57}6]
But the latter puts 10(3)n7 = {136} and 2 in r7c4 which leaves no place for 2 in n7.
-> r78c4 = [17]
-> 18(3)n7 = [{56}7]
-> 10(3)n7 = {127}
-> r9c789 = [6{39}]
-> r8c7 = 4
Also r7c56 = {26}

4. HP r8c89 = {12}
Since r9c89 = {39} -> Only solution for 17(4)r6c9 = [4823]
-> 22(4)n9 = [{57}19]
-> 25(5)n7 = [{349}18]

5. Given:
a) r7c5 from (26)
b) r7c4 = 1
c) r6c9 = 4
-> Only solutions for 9(3)r6c4 are [612] or [216]. I.e., r6c5 = 1

5. Innies n4 -> r4c1 = 1
-> (26) in n4 only in 20(4)n4
-> One of (26) in r5c3 and the other in r6c123
-> (26) locked in r6c1234
-> 15(2)n6 = {78}
-> 20(4)n4 = {2369} with one of (26) in r5c3

6. Since 1 in r6c5 and in r7c4 -> 1 not in 40(5)
-> 4 not in 40(5)
-> 4 in n5 in r4c56
-> 12(2)r4c2 = {57}
-> 12(2)r5c1 = [48]
Also (15) in n6 in r5c789
-> r5c3789 = [6][125] or [2][561]
-> r5c456 = {379}
-> r6c6 = 5

7. Outies n3 = r23c6 = +13(2)
-> HS 1 in c6 -> r1c6 = 1
Remaining Outies n1 -> r2c45 = +11(2)
-> Remaining Innies n2 = r3c45 = +9(2)
*Note* that both r1c45 and r2c45 = H+11(2)

Since 4 in r4c56 -> r3c45 cannot be {45}
-> 5 in n2 in r12c45
-> 6 in n2 in r12c45
-> r23c6 = +13(2) = {49}
-> r3c45 = [27]
-> 9(3)r6c4 = [612]
-> 13(3)r3c5 = [742]
-> r4c4 = 8
-> r7c6 = 6
Also 20(4)n4 = [6{239}]
-> 7(2)n6 = [25]
-> 19(4)n6 = [{369}1]

8. 5 in c1 only in r123c1
-> 14(4)r1c1 = [{256}1]
Remaining Innies n1 = r12c3 = +10(2)
-> HS 8 in n1 -> r3c3 = 8
Also r8c23 = [65]
-> 12(2)r4c2 = [57]
-> r12c3 = [91]
Innies r1 -> r1c123 = +15(3) which can only be [249]
-> r2c1 from (56)
-> 12(3)n2 = [561]
-> r2c45 = [38]
-> r23c2 = [73]
-> Remaining Innies r2 = r2c19 = +11(2) can only be [56]
-> r3c1 = 6

9. Also 18(3)n3 = [{38}7]
-> NS 9 in c9 -> r4c9 = 9
-> r3c9 = 1
Also r4c78 = [36]
-> r1c78 = [83]
-> r6c78 = [78]
-> r7c78 = [57]
-> HS r3c8 = 5
-> NS r2c8 = 4
-> 15(3)r2 = [924]
etc.


Top
 Profile  
Reply with quote  
 Post subject: Re: Assassin 359
PostPosted: Tue Sep 25, 2018 9:35 pm 
Offline
Grand Master
Grand Master

Joined: Wed Apr 23, 2008 6:04 pm
Posts: 1893
Location: Lethbridge, Alberta, Canada
Ed wrote:
I can still make a symmetrical puzzle!
That made it easier for me to colour the cages on my Excel worksheet, with diagonally opposite cages getting the same colours. :)

My solving path was very routine. At first I wondered where to go next after step 2, but then I went back to step 1 and added steps 1t ->, after which things were straightforward.

Here is my walkthrough for Assassin 359:
Prelims

a) R4C23 = {39/48/57}, no 1,2,6
b) R5C12 = {39/48/57}, no 1,2,6
c) R5C89 = {16/25/34}, no 7,8,9
d) R6C78 = {69/78}
e) 9(3) cage at R6C4 = {126/135/234}, no 7,8,9
f) 10(3) cage a R9C1 = {127/136/145/235}, no 8,9
g) 14(4) cage at R1C1 = {1238/1247/1256/1346/2345}, no 9

1a. 45 rule on N4 1 innie R4C1 = 1
1b. 45 rule on N1 2 remaining innies R12C3 = 10 = {19/28/37/46}, no 5
1c. R12C3 = 10 -> R2C45 = 11 = {29/38/47/56}, no 1
1d. 45 rule on N6 1 innie R6C9 = 4, clean-up: no 3 in R5C89
1e. 45 rule on N9 2 remaining innies R89C7 = 10 = {19/28/37/46}, no 5
1f. R89C7 = 10 -> R8C56 = 12 = {39/48/57}, no 1,2,6
1g. 1 in R6 only in R6C456, locked for N5
1h. 45 rule on N3 2 outies R23C6 = 13 = {49/58/67}, no 1,2,3
1i. 45 rule on N7 2 outies R78C4 = 8 = {17/26/35}, no 4,8,9
1j. 45 rule on R123 2 remaining innies R3C45 = 9 = {18/27/36/45}, no 9
1k. 45 rule on R789 2 remaining innies R7C56 = 8 = [17]/{26/35}, no 4 in R7C5, no 1,4,8,9 in R7C6
1l. 40(7) cage at R3C4 must contain 9, locked for N5
1m. 4,8,9 in N8 only in R8C56 + R9C456, CPE no 4,8,9 in R9C7, clean-up: no 1,2,6 in R8C7
1n. R78C4 = {17/26/35}, R7C56 = [17]/{26/35} -> combined hidden cages R78C4 + R7C56 = {17}{26}/{17}{35}/{26}{35}
1o. R8C56 = {39/48} (cannot be {57} which clashes with R78C4 + R7C56), no 5,7
1p. 17(3) cage at R9C4 = {179/269/359/458} (cannot be {278/467} which clash with R78C4 + R7C56, cannot be {368} which clashes with R8C56)
1q. 18(3) cage at R8C2 = {279/369/468/567} (cannot be {189/378/459} which clash with R8C56}, no 1, clean-up: no 7 in R7C4
1r. 1 in R8 only in R8C89, locked for N9, clean-up: no 9 in R8C7
1s. 22(4) cage at R8C5 = {2389/3469/3478}, CPE no 3 in R8C89
1t. 45 rule on R9 3 innies R9C789 = 18 = {279/369/567} (cannot be {378} which clashes with R89C7 = {37} CCC, cannot be {459} because no 4,5,9 in R9C7, cannot be {468} which clashes with R89C7 = [46] CCC), no 4,8
1u. 17(3) cage = {458} (only remaining combination, cannot be {179/269/359} which clash with R9C789), locked for R9 and N8
1v. Naked pair {39} in R8C56, locked for R8, N8 and 22(4) cage at R8C5, clean-up: no 7 in R89C7
1w. 9 in R9 only in R9C89, locked for N9
1x. 1 in N8 only in R7C45, locked for R7, CPE no 1 in R6C4
1y. 9(3) cage at R6C4 = {126/135}, 1 locked for C5, clean-up: no 8 in R3C4
1z. 7 in N8 only in R7C6 + R8C7, CPE no 7 in R345C4, clean-up: no 2 in R3C5
1aa. R9C789 = {279/369}
1ab. R9C7 = {26} -> no 2,6 in R9C89
1ac. 18(3) cage at R8C2 = {567} (only remaining combination, cannot be {468} which clashes with R8C7), locked for R8, 5 also locked for N7, clean-up: no 6 in R7C4
1ad. Killer pair 6,7 in R8C23 and R9C123, locked for N7
1ae. 2 in N8 only in R7C456, locked for R7

2. 3 in N6 only in 19(4) cage at R4C7 = {1369/2359} (cannot be {1378} = {378}1 which clashes with R4C23, cannot be {2368} which clashes with R6C78), no 7,8
2a. 1 of {1369} must be in R5C7 -> no 6 in R5C7
2b. R6C78 = {78} (hidden pair in N6), locked for R6
2c. 2,6 in N4 only in 20(4) cage at R5C3 = {2369/2567} (cannot be {2468} because 4,8 only in R5C3), no 4,8
2d. 7 of {2567} must be in R5C3 -> no 5 in R5C3
2e. 40(7) cage at R3C4 must contain 8, locked for N5
2f. 40(7) cage must contain 7, CPE no 7 in R4C6
2g. 13(3) cage at R3C5 = {247/256/346} (cannot be {238} = 8{23} which clashes with 19(4) cage), no 8, clean-up: no 1 in R3C4 (step 1j)
2h. 1 in N2 only in 12(3) cage at R1C4, locked for R1, clean-up: no 9 in R2C3 (step 1b)
2i. 20(4) cage at R5C3 = {2369} (only remaining combination, cannot be {2567} = 7{256} which clashes with 9(3) cage at R6C4), locked for N4
2j. 5 in R6 only in R6C456, locked for N5
2k. 40(7) cage must contain 5, CPE no 5 in R3C6 + R6C4, clean-up: no 8 in R2C6 (step 1h)
2l. Naked quad {2369} in R6C1234, locked for R6, 9 also locked for N4
2m. 9(3) cage at R6C4 = [216/351/612]
2n. 13(3) cage = {247/346} (cannot be {256} = 5{26} which clashes with 9(3) cage), no 5, clean-up: no 4 in R3C4 (step 1j)
2o. 13(3) cage = {247/346}, CPE no 4 in R5C5

3. 25(5) cage at R7C1 = {13489} (only possible combination), no 2 -> R7C4 = 1, 3 locked for R7 and N7, R8C4 = 7 (step 1i), clean-up: no 4 in R2C5 (step 1c)
3a. 10(3) cage at R9C1 = {127} (hidden triple in N7), locked for R9, R9C7 = 6 -> R8C7 = 4 (step 1e), R8C1 = 8, clean-up: no 4 in R5C2
3b. R4C1 = 1 -> 14(4) cage at R1C1 = {1256/1346} (cannot be {1247} which clashes with R9C1), no 7, 6 locked for C1 and N1, clean-up: no 4 in R12C3 (step 1b)
3c. R6C5 = 1 (hidden single in C5), R6C6 = 5, clean-up: no 4 in R3C5 (step 1j), no 8 in R3C6 (step 1h)
3d. 9(3) cage at R6C4 = [216/612], no 3, CPE no 2,6 in R45C5
3e. 40(7) cage at R3C4 = {2356789} (only remaining combination), no 4
3f. R5C1 = 4 (hidden single in R5) -> R5C2 = 8
3g. 14(4) cage = {1256} (only remaining combination), 2,5 locked for C1 and N1, clean-up: no 8 in R12C3 (step 1b)
3h. R3C3 = 8 (hidden single in N1)
3i. Naked pair {57} in R4C23, locked for R4
3j. 19(4) cage at R4C7 (step 2) = {1369/2359}
3k. 1,5 of 19(4) cage only in R5C7 -> R5C7 = {15}
3l. 3 in N6 only in R4C789, locked for R4 -> R4C5 = 4
3m. 3 in N5 only in R5C456, locked for R5 and 40(7) cage at R3C4, clean-up: no 6 in R3C5 (step 1j)
3n. Killer pair 2,6 in R5C3 and R5C89, locked for R5
3o. Naked pair {26} in R47C6, locked for C6, clean-up: no 7 in R23C6 (step 1h)
3p. Naked pair {49} in R23C6, locked for C6 and N2 -> R8C56 = [93], R5C456 = [937], 17(3) cage at R9C4 = [458], R3C5 = 7, R3C4 = 2 (step 1j), R46C4 = [86], R4C6 = 2
3q. 2 in N6 only in R5C89 = {25}, locked for R5 -> R5C3 = 6, R8C23 = [65], R4C23 = [57], clean-up: no 3 in R12C3 (step 1b)
3r. R12C3 = [91]
3s. R6C9 = 4 -> 17(4) cage at R6C9 = {2348} (only remaining combination, cannot be {1349} because 3,9 only in R9C9, cannot {1457} because 5,7 only in R7C9) -> R789C9 = [823], R5C89 = [25], R89C8 = [19]
3t. 12(3) cage at R1C4 = [381/561]
3u. 18(3) cage at R1C7 = {378/567} (cannot be {468} which clashes with R1C5), no 2,4, 7 locked for R1 and N3
3v. Naked pair {69} in R24C9, locked for C9 -> R13C9 = [71]
3w. R2C7 = 2 (hidden single in N3) -> R2C68 = 13 = [94]

and the rest is naked singles.

Rating Comment:
I'll rate my WT for A359 at Easy 1.25; the crossover clashes within N9 were my technically hardest steps.


Top
 Profile  
Reply with quote  
 Post subject: Re: Assassin 359
PostPosted: Fri Sep 28, 2018 6:48 am 
Offline
Grand Master
Grand Master

Joined: Wed Apr 16, 2008 1:16 am
Posts: 1040
Location: Sydney, Australia
wellbeback wrote:
I'm sure there's a term for what Step 2 Line 2 does. Is this IOD?
CCC (see Andrew's step 1t). I saw that spot differently and used IOU (my step 6). Funny how we nearly always see this differently. Brains. I used a path quite similar to wellbeback, at least in the beginning.

a359 WT:
Preliminaries courtesy of SudokuSolver
Cage 15(2) n6 - cells only uses 6789
Cage 7(2) n6 - cells do not use 789
Cage 12(2) n4 - cells do not use 126
Cage 12(2) n4 - cells do not use 126
Cage 9(3) n58 - cells do not use 789
Cage 10(3) n7 - cells do not use 89
Cage 14(4) n14 - cells do not use 9

Routine cage clean-up not done unless stated.
1. "45" on n6: 1 innie r6c9 = 4
1a. no 3 in 7(2)n6

2. "45" on n7: 2 outies r78c4 = 8 (no 4,8,9)

3. "45" on n6789: 2 innies r7c56 = 8 (no 4,8,9)

4. "45" on n69: 2 innies r89c7 = 10 (no 5)

5. 8 & 9 in n8 only in r8c56 + r9c456: r9c7 sees all these -> no 8,9 in r9c7 (CPE)
5a. no 1,2 in r8c7 (h10(2))
[edit: Andrew noticed that I missed the 4 in this same spot. I did! I knew the 8 was the important elimination because of step 6. Thanks Andrew!]

No doubt Andrew will see this next step differently (and he did!).
6. "45" on r9: remembering h10(2)r89c7: 1 outie r8c7 + 8 = 2 innies r9c89
6a. 1 innie and 1 outie are in the same nonet -> no 8 in r9c89 (IOU)

7. 8 in r9 only in 17(3)n8 : 8 locked for n8
7a. = {278/368/458}(no 1,9)

8. "45" on n69: 2 outies r8c56 = 12 and must have 9 for n8 = {39} only: both locked for r8, n8 and no 3 in r9c7
8a. no 5 in r7c56 nor r78c4 (two h8(2))

9. hidden triple {458} for n8 in r9c456: all locked for r9
9a. r89c7 = h10(2) = [46/82]

10. 18(3)r8c2: {468} blocked by r8c7
10a. = {567} only: all locked for r8: 5 locked for n7
10b. r7c4 = (12) (h8(2)r78c4)

11. 10(3)n7 = {127/136}: must have 1, 1 locked for r9 & n7

12. 25(5)r7c1: must have 4,8,9 for n7
12a. = {13489} only (no 2,6,7) -> r78c4 = [17]
12b. 3 locked for n7 and r7; 9 locked for r7

13. 10(3)n7 = {127} only: 2 & 7 locked for r9
13a. r89c7 = [46] (h10(2))
13b. r8c1 = 8
13c. no 4 in r5c2
13d. r6789c9 = [4823] only valid permutation
13e. r89c8 = [19]

14. 9(3)r6c4 must have 2,6 for r7c5 = {126} only
14a. r6c5 = 1

15. 40(7)r3c4 = {2356789} only (no 4)

16. "45" on n5: 4 outies = 17. r7c56 = {26} = 8
16a. -> r3c45 = 9 (no 8,9), no 2,5 in r3c5

17. 13(3)r3c5: must have 4 for n5 -> no 4 in r3c5
17a. = {247/346}(no 5,8,9)
17b. 7 in {247} must be in r3c5 -> no 7 in r4c56
17c. r3c45 = [27]/{36}
17d. no 5 in r3c4 (h9(2))
17e. 4 locked for r4
17f. no 8 in 12(2)r4c23

18. "45" on n4: 1 innie r4c1 = 1

19. 20(4)n4 must have 2 & 6 for n4: but [4]{268} blocked by r6c4
19a. = {2369/2569}(no 4,8)

20. hidden single 4 in r5 -> r5c1 = 4, r5c2 = 8

21. r4c1 = 1 -> r123c1 = 13 = {256} only: locked for c1 and n1

22. "45" on n14: 2 innies r12c3 = 10 = {19/37}(no 4,8)

23. "45" on r1: remembering the h10(2)r12c3 -> 1 outie r2c3 + 5 = 2 innies r1c12
23a. 1 outie and 1 innie are in the same nonet -> no 5 in r1c1 (IOU)

24. "45" on r1, 3 innies r1c123 = 15 = [249] only valid permutation
24a. r2c3 = 1 (h10(2)r12c3)

25. r12c3 = 10 -> r2c45 = 11: but {56} blocked by r2c1
25a. = {38}/[47] (no 2,5,6; no 4 in r2c5)
25b. 15(3)r2c6: {456} blocked by r2c1

cracked. Much easier now.
Cheers
Ed


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 9 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