Killer X-mas tree

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Ruud
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Killer X-mas tree

Post by Ruud »

Here is a V2X of this week's Assassin.

It is solvable by logic, but you need a lot of it. Fortunately, you will have a little more time now with the upcoming Holidays, for which I wish you all the best.

Image

3x3:d:k:4608:4609:4609:4609:3332:5125:5125:5125:5128:4608:4362:4609:3084:3332:3332:5125:2064:5128:4608:4362:3084:3084:4374:3351:3351:2064:5128:3099:4362:3869:4374:4374:5152:5153:2064:3363:3099:3869:3869:4135:5152:5152:5153:5153:3363:3099:6702:4135:4135:5152:4658:4658:4404:3363:6702:6702:4135:3897:3642:3899:4658:4404:4404:6702:2112:3897:3897:3642:3899:3899:3910:4404:2112:2112:3658:3658:3642:2893:2893:3910:3910:

Ruud
“If the human brain were so simple that we could understand it, we would be so simple that we couldn't.” - Emerson M Pugh
Afmob
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Location: MV, Germany

Post by Afmob »

Although my walkthrough is quite short, it was tough to find the solution since it took me a long time to find the key moves.

A82 V2X Walkthrough:

1. C6789
a) 8(3) = 1{25/34} -> 1 locked for C8
b) Innies C89 = 17(2) = {89} locked for C8
c) 15(3) @ R8C8: R9C9 <> 1 because R89C8 <= 13
d) Innies C6789 = 10(3) <> 8,9
e) Outies N3 = 16(2+1): R1C6 <> 1 because R4C8 <= 5
f) Killer pair (89) locked in 20(3) + R1C8 for N3
g) 20(3) @ N3 <> 3 because {389} blocked by R1C8 = (89)
h) 13(2): R3C6 <> 4,5

2. C1234
a) 8(3) = 1{25/34} -> 1 locked for N7
b) Innies C12 = 9(2) <> 9
c) Innies = 9 = R4C4
d) 17(3) @ C4 = 9{17/26/35}
e) 14(2): R9C3 <> 5

3. R6789+D/ !
a) Killer pair (56) of 14(2) blocks {56} of 11(2)
b) 18(3): R6C7 <> 1,2 because R6C6+R7C7 <= 15
c) ! 17(4): R78C9 <> 6,7 since it sees all 6,7 of C8

4. C56
a) 20(4) @ N5: R45C6 >= 5 because R56C5 <= 15
b) Outies C6789 = 10(3): R2C6 <> 6,7 because R45C6 >= 5
-> R45C6 <= 9
c) 20(4) @ N5: R56C5 >= 11 (step 4b) -> R56C5 <> 1,2

5. C789 !
a) Innies C9 = 12(3) <> {345} because it's blocked by Killer pair (45) of 20(3) @ C9
b) Innies C9 = 12(3): R9C9 <> 4,5 because R78C9 <> 6,7
c) ! Innies C9 <> 2{37/46} because (67) must be in R9C9 @ 15(3) but that's not possible
because 6{27/45} needs 2/4 and 7{26/35} needs 2/3
d) Innies C1 = 1{29/38/47/56} -> 1 locked for C9+N9
e) Hidden Single: R4C8 = 1 @ N6
f) Killer pair (45) locked in 20(3) + 8(3) for N3
g) 13(2) = {67} locked for R3
h) Outies N3 = 15(2) = [87/96] (because R4C8 = 1)

6. N36+D/
a) 20(4) = {1289} -> 1,2 locked for C7+N3; 8,9 locked for R1
b) 8(3) = {134}, {34} locked for C8+N3
c) 20(3) @ N3 = 5{69/78} -> 5 locked for C9
d) Innies N6 = 12(3) = 1[47/56/65/92] -> R6C7 = (4569)
e) Hidden Single: R7C3 = 9 @ D/
f) 16(4) = {1249} -> 1,2,4 locked between R6+N5 -> R6C56 <> 1,2,4
g) Hidden Single: R5C5 = 8 @ D/
h) R5C8 = 9, R1C8 = 8, R1C6 = 9
i) 15(3) = 7{26/35} -> 7 locked for N9

7. C789
a) 20(3) @ N3 = {569} locked for C9+N3
b) R3C7 = 7, R3C6 = 6
c) 13(3) = 2{38/47} -> 2 locked for C9+N6
d) 18(3) = {567} -> R6C6 = 7, {56} locked for C7
e) 20(3) @ N6 = {389} -> R5C7 = 3, R4C7 = 8
f) 15(3) @ R8C8 = {357} -> R9C9 = 3, R9C8 = 7, R8C8 = 5
g) 11(2) = [29] -> R9C6 = 2, R9C7 = 9
h) 15(3) @ R7C6 = {348} -> R8C7 = 4; 3,8 locked for C6+N8

8. C456
a) 13(3) = 7{15/24} -> 7 locked for C5+N2
b) 14(3) = {149} -> R8C5 = 9; {14} locked for C5+N8
c) 14(2) = {68} -> R9C4 = 6, R9C3 = 8
d) 15(3) @ R7C4 = {357} -> R8C4 = 7, R7C4 = 5, R8C3 = 3

9. C123+D\
a) 8(3) = {125} -> R8C2 = 2, 1 locked for R9+N7
b) 26(4) = {4679} -> R8C1 = 6, R6C2 = 9
c) 15(3) = 6{27/45} -> 6 locked for N4
d) R7C7 = 6
e) 17(3) = {458} -> R2C2 = 4, R3C2 = 8, R4C2 = 5
f) 15(3) = {267}

10. Rest is singles without considering the diagonals.

Rating: 1.5, it had only few advanced moves but those were difficult to find.
Last edited by Afmob on Fri Dec 28, 2007 8:30 am, edited 1 time in total.
CathyW
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Location: Hertfordshire, UK

Post by CathyW »

Merry Christmas everyone and a Happy New Year (might not get a chance to visit the site again until after the festivities!)

Sorry I haven't been around so much lately. More time Ruud?!!! Not in this household!

All the best
Cathy xx
Nasenbaer
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Location: Fellbach (Deutschland)

Post by Nasenbaer »

Hi Afmob, here are some comments on your walkthrough. (Tiny font intentionally removed)

After your work with number 9 I would insert this:
2.f) 9 locked in r7c3 r1c9 for D/ -> no 9 in r1c3 and r7c9 (I know, it will be removed in 6.e) but it's such a nice move) :wink:
5.g) 13(2) = {67} locked for R3
This also removes 6,7 from r4c6 by using D/
5.h) Outies N1 = 15(2) = [87/96] (because R4C8 = 1)
Typo, it should read
5.h) Outies N3 = 15(2) = [87/96] (because R4C8 = 1)

Sometimes it was a little hard to find the cage you used. It would be easier if you would write something like N9: 15(3) or 15(3) @ r8c8 (you did that sometimes). But that is just my opinion.

Cheers,
Nasenbaer
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