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Start of an occasional series - Messy One. Must get a SudokuSolver Score from 0.95-1.05 and is messy (NOT symmetrical). Anyone's welcome to make #2 [edit: only 1 puzzle/maker allowed]. Messiest Winner Poll after #9 [edit: or 3 months, whichever comes first]

Messy One #1 SS(v3)score 1.02
Killer X (1-9 cannot repeat on the diagonals)
NOTE: diagonal cage 8(3) in n5
My key move in tt (SPOILER) : Locked Cages on 8 in the two 9(2) cages in n4 -> 1 locked for n4



PS code: select and paste into solver
3x3:d:k:2817:2817:3330:4867:4867:6916:6916:6916:6916:773:4614:3330:3847:4867:6916:4872:4872:4872:773:4614:4614:3847:4867:4105:4105:4105:4872:4874:2315:2315:2060:4867:5389:5389:5646:5646:4874:4623:3856:3856:2060:5389:5389:3601:5646:4874:4623:3346:3346:3346:2060:3601:3601:5646:6931:4623:4623:6931:7188:4885:4885:4885:3350:6931:6931:6931:6931:7188:4885:5143:4885:3350:4632:4632:4632:4632:7188:7188:5143:5143:5143:


Solution:
836 457 291
297 618 543
154 932 687
945 163 872
368 729 154
721 845 369
419 386 725
672 591 438
583 274 916

Cheers
Ed

We can't have a Killer on our new home without a walkthrough, can we?

Nice idea Ed though it will be quite difficult to get the SS rating right since the range of accepted ratings is quite small. This is probably one of the rare cases where it's harder to create a Killer than to solve it.

Messy One #1 Walkthrough:

1. R123
a) Outies = R4C5 = 6
b) 3(2) = {12} locked C1+N1
c) 11(2) <> 9
d) 19(5) = 136{27/45} -> 1,3 locked for N2

2. R456 !
a) Innies = 8(2) <> 4,8,9
b) Outies N56 = 9(2) = [63/72/81]
c) 9 locked in 19(3) @ N4 for C4 -> 19(3) = 9{37/46}
d) 9(2) <> 3
e) ! Outies N56 = 9(2) <> {36} because it'S a Killer pair of 19(3)
f) 15(2) = {78} locked for R5
g) Outies N6 = 12(2) <> 1,2,6; R4C6 <> 4,5
h) 13(3) must have 1 xor 2 because R6C3 = (12) -> R6C45 <> 1,2
i) 1,2 locked in 8(3) @ N5 = {125} locked for N5+D\
j) Outies N6 = 12(2) <> 7

3. C456 !
a) 15(2) @ N1 = {69} locked for C4+N2 because R5C4 = (78) blocks {78}
b) ! Outies N9 = 7(2) = {16/25} because {34} blocked by Killer pair of Outies N6
c) 28(4) = {4789} locked for N8 because {5689} blocked by Killer pair of Outies N9
d) Innies N89 = 10(3) = {235} locked for C4+N8
e) 3 locked in Outies N6 @ C6 = 12(2) = {39} locked for C4+N5+21(4)
f) 13(3) = 4{18/27} -> 4 locked for R6
g) R4C4 = 1

4. N4
a) 9(2) <> 8
b) Hidden Single: R5C3 = 8 @ N4, R5C4 = 7, R1C4 = 4
c) 13(3) = {148} -> R6C3 = 1, R6C4 = 8, R6C5 = 4
d) Hidden Single: R9C6 = 4 @ C6

5. N12
a) 19(5) = {13456} -> {135} locked for C5+N2
b) 11(2) <> 7; R1C2 <> 6
c) 13(2) <> 5; R2C3 <> 9
d) 5 locked in R13C2 for C2
e) Hidden Single: R4C3 = 5 @ N4 -> R4C2 = 4

6. R456
a) R5C5 = 2, R6C6 = 5
b) Innies = 8(2) = [62] -> R5C2 = 6, R6C2 = 2
c) 19(3) = {379} locked for C1
d) Innies N6 = 9(2) = [81] -> R4C7 = 8, R5C7 = 1
e) Outies N4 = 10(2) <> 4,8; R6C2 <> 9

7. R789
a) 18(4) must have 5 xor 6 because R9C1 = (56) -> R9C34 <> 5,6
b) 5 locked in R78C4 for 27(6)
c) Hidden Single: R9C1 = 5 @ N9
d) 18(5) = 35{19/28} -> 3 locked for R9
e) 19(5) = 136{27/45} because R78C6 = (16); R7C8 = (25) and R7C7+R8C8 <> 6
-> 3 locked for N9+D\
f) Hidden Single: R9C8 = 1 @ N7
g) 18(4) = {2358} -> R9C2 = 8; 2 locked for R9
h) 20(4) = {1469} -> R8C7 = 4, {69} locked for R9+N9
i) 13(2) = {58} locked for C9+N9

8. R123
a) Hidden Single: R1C1 = 8 @ N1 -> R1C2 = 3
b) 27(5) = 178{29/56} -> R2C6 = 8, R1C9 = 1
c) R1C5 = 5
d) 27(5) = {12789} -> {279} locked for R1, 9 locked for N3
e) Hidden Single: R7C2 = 1 @ N7 -> R7C3 = 9

9. Rest is singles.

Rating: 1.0. I used Killer pairs to crack it.

PS: It was tough to get the right tiny text size without appearing too small. I used 14 here.

Nice, enjoyable, and (above all!) messy killer, Ed! Thanks!

Just to give Afmob a bit of company, here's my WT. I used a combined cage move (step 5), which almost certainly is not necessary, but which added to the fun, so I thought "why not?".

Like Afmob, I'll rate this one at 1.0.

May 15, 2008: Corrections from Andrew applied (many thanks!)

Here's the way I did it:

Messy One #1 Walkthrough

_________________
Cheers,
Mike

When I saw this introduction I assumed, although I don't know if Ed intended it, that each puzzle creator can contribute one puzzle toward the Messiest Winner Poll. If so, then maybe Ed should reduce the number from 9 to 5 or 6? Then the next set could start with each creator welcome to contribute another Messy One.

I only set up files for the first two Messy Ones this week. Now I've done #1 I hope to try #2 soon.

This was a fun puzzle and a fairly easy one. Even so the solving path is fairly well defined so that my route was very similar to those already posted by Afmob and Mike.


An interesting combined cage move. As Mike said, it's not necessary but it does reduce R56C2 to a naked pair more quickly.

I'll also rate Messy One #1 at 1.0. I thought about a lower rating but it's still a reasonably long path and harder than newspaper puzzles or those on http://www.sudoku.org.uk so I feel that 1.0 is justified.

I wasn't going to post my walkthrough, but have changed my mind so here it is. I've included eliminations on the diagonals for those who do their own eliminations manually; ones on the diagonals are particularly easy to overlook, I often forget them.

It's my first walkthrough for many months, probably over a year, that doesn't include the word killer although it does still have half a dozen clashes.

Prelims

a) R1C12 = {29/38/47/56}, no 1
b) R12C3 = {49/58/67}, no 1,2,3
c) R23C1 = {12}, locked for C1 and N1, clean-up: no 9 in R1C12
d) R12C4 = {69/78}
e) R4C23 = {18/27/36/45}, no 9
f) R5C34 = {69/78}
g) R78C9 = {49/58/67}, no 1,2,3
h) R456C1 = {289/379/469/478/568}, no 1
i) 8(3) diagonal cage in N5 = {125/134}, 1 locked for N5 and D\
j) 28(4) cage in N8 = {4789/5689}, no 1,2,3, 8,9 locked for N8
k) 19(5) cage at R1C4 = {12349/12358/12367/12457/13456}, 1 locked for N2
l) 19(5) cage at R7C6 = {12349/12358/12367/12457/13456}, must contain 1

1. 45 rule on R123 1 outie R4C5 = 6, clean-up: no 3 in R4C23, no 9 in R5C3

2. 28(4) cage in N8 = {4789/5689}
2a. 6 of {5689} must be in R9C6 -> no 5 in R9C6

3. 45 rule on R789 2 innies R7C23 = 10 = {19/28/37/46}, no 5
3a. R56C2 = 8 = {17/26/35}, no 4,8,9

4. 45 rule on N9 2 outies R78C6 = 7 = {16/25/34}, no 7
4a. R7C78 + R8C8 = 12 = {129/138/147/156/237/345} (cannot be {246} which clashes with R78C6)
4b. 1 of {129} must be in R7C8 -> no 9 in R7C8

5. 45 rule on N4 2 innies R56C3 = 9 = [63/72/81], no 9 in R5C3, R6C3 = {123}

6. 9 in N4 locked in R456C1, locked for C1
6a. R456C1 = {379/469}, no 5,8
6b. R56C3 (step 5) = [72/81] (cannot be [63] which clashes with R456C1), no 3,6, clean-up: no 9 in R5C4

7. Naked pair {78} in R5C34, locked for R5, clean-up: no 1 in R6C2 (step 3a)
7a. R23C4 = {69} (cannot be {78} which clashes with R5C4), locked for C4 and N2

8. 45 rule on N6 2 outies R45C6 = 12 = {39}/[75/84], no 2, no 4,5 in R4C6
8a. R45C7 = 9 = [36/45/54/72/81], no 9, no 1,2 in R4C7, no 3 in R5C7

9. 45 rule on N8 3 innies R789C4 = 10 = {127/235} (cannot be {145} which clashes with 28(4) cage), no 4, 2 locked for C4 and N8, clean-up: no 5 in R78C6 (step 4)
9a. R7C78 + R8C8 (step 4a) = {129/156/237/345} (cannot be {138/147} which clash with R78C6), no 8

10. 45 rule on N5 3 innies R5C4 + R6C45 = 19 = {379/478} (cannot be {289} because 2,9 only in R6C5), no 2,5, 7 locked for N5, clean-up: no 5 in R5C6 (step 8)
10a. 9 of {379} must be in R6C5 -> no 3 in R6C5

11. 2,5 in N5 locked in 8(3) diagonal cage = {125} (only remaining combination), locked for D\, clean-up: no 6 in R1C2

12. R7C78 + R8C8 (step 9a) = {237/345} (cannot be {129/156} because 1,2,5 only in R7C8), no 1,6,9
12a. 2,5 only in R7C8 -> R7C8 = {25}
12b. 3 locked in R7C7 + R8C8, locked for N9, D\ and 19(5) cage -> no 3 in R78C6, clean-up: no 8 in R1C2, no 4 in R78C6 (step 4)
12c. 3 in N1 locked in R13C2, locked for C2, clean-up: no 5 in R56C2 (step 3a), no 7 in R7C3 (step 3)

13. Naked pair {16} in R78C6, locked for C6 and N8, clean-up: no 7 in R789C4 (step 9), no 5 in 28(4) cage in N8 (step 2)

14. Naked triple {235} in R789C4, locked for C4 -> R4C4 = 1, clean-up: no 8 in R4C23, no 9 in R6C5 (step 10)

15. R5C3 = 8 (hidden single in N4), R5C4 = 7, R6C3 = 1 (step 6b), clean-up: no 5 in R12C3, no 7 in R6C2 (step 3a), no 2,9 in R7C2 (step 3)

16. Naked pair {26} in R56C2, locked for C2, N4 and 18(4) cage -> no 2,6 in R7C3, clean-up: no 7 in R4C23, no 4 in R456C1 (step 6a), no 4,8 in R7C2, no 4 in R7C3 (both step 3)
16a. Naked pair {45} in R4C23, locked for R4, clean-up: no 4,5 in R5C7 (step 8a)
16b. Naked triple {379} in R456C1, locked for C1, clean-up: no 4 in R1C2
16c. 5 in C1 locked in R789C1, locked for N7

17. Naked pair {48} in R6C45, locked for R6 and N5

18. Naked pair {39} in R45C6, locked for C6 and 21(4) cage -> no 3 in R4C7, clean-up: no 6 in R5C7 (step 8a)

19. Naked pair {39} in R5C16, locked for R5

20. Naked pair {39} in R4C6 and R7C3, locked for D/

21. 2 in R4 locked in R4C89, locked for N6 -> R5C7 = 1, R4C7 = 8 (step 8a)
21a. R9C8 = 1 (hidden single in N9)
21b. 8 in N9 locked in R789C9, locked for C9

22. 1,3 in C5 locked in R123C5 with 6 in R4C5 -> 19(5) cage = {13456} (only remaining combination, cannot be {12367} because R1C4 only contains 4,8) -> R1C4 = 4, R123C5 = {135}, locked for C5 and N2 -> R5C5 = 2, locked for D/, R6C6 = 5, R56C2 = [62], R6C45 = [84], 8 locked for D/, clean-up: no 7 in R1C2, no 9 in R2C3
22a. R9C6 = 4 (hidden single in C6)

23. 18(3) cage in N1 = {378/459/567} (cannot be {369/468} which clash with R1C12)
23a. 3,5 only in R3C2 -> R3C2 = {35}
23b. Naked pair {35} in R13C2, locked for C2 -> R4C23 = [45]
[R4C3 had been a hidden single in C3 since step 16c.]
23c. 4 of {459} must be in R3C3 -> no 9 in R3C3
23d. 4 in N1 locked in R23C3, locked for C3

24. 3 in R9 locked in R9C34
24a. 18(4) cage at R9C1 = {2358/2367}, no 9
24b. 2,3 only in R9C34 -> R9C34 = {23}, locked for R9

25. 5 in C4 locked in R78C4, locked for 27(6) cage -> no 5 in R78C1

26. R9C1 = 5 (hidden single in C1), locked for D/, R9C2 = 8 (step 24a)
26a. Naked pair {46} in R78C1, locked for C1 and N7 -> R1C1 = 8, R1C2 = 3, R3C2 = 5

27. Naked pair {17} in R78C2, locked for C2 and N7 -> R2C2 = 9, R3C3 = 4 (step 23), both locked for D\, R23C4 = [69], R12C3 = [67], R2C8 = 4, R5C89 = [54], R7C8 = 2, clean-up: no 9 in R78C9
27a. R3C7 = 6 (hidden single in D/)

28. Naked pair {37} in R7C7 + R8C8, locked for N9 -> R9C79 = [96], R9C5 = 7, R8C7 = 4 (hidden single in C7), R78C1 = [46], R78C6 = [61], R78C2 = [17], 7 locked for D/, R7C3 = 9 (step 3), locked for D/

and the rest is naked singles without using the diagonals

I didn't have in mind one only for each puzzle maker...but now that you mention it...what a great idea! Now I can harrass everybody who has never made a puzzle to start. Lets see...who should I pick on first....

OK - lets change it to at least every 3 months a Messiest-One Winner Poll. One puzzle per puzzle maker. Roll of honour to be included into the ratings update thread (when it finally gets going!).

Now to a few things to wrap up MO#1
1) Technically not eligible for this thread: SS(v3.1)score = 0.91. Might put it into the running for Messiest Winner if everyone decides to vote based on easiest.

2) Mike pointed out my tt key move (I called 'direct links') is generally called Locked Cages. A really great tutorial on sudopedia here. Highly recommended. Very familiar examples!

In MO#1 it works like this from this spot: the 8 in n4 is only in the two 9(2) cages (one hidden) in n4 -> one of those cages must have 1 -> 1 locked for n4




3) Thanks for the Walk-throughs guys. I missed the cage block in n4 that Afmob and Andrew used to break it open. Mike
used cage-combining to eliminate {17} from r56c2 where-as I used Locked cages. As usual in fun puzzles - 3 ways to go!

Cheers
Ed