Posted: Thu Jun 07, 2007 6:35 pm
by udosuk
Greetings everyone,
This is my very first post here.
Been stalking even before the opening of this section (more than a whole year!

) and finally drag myself to actually register.
As I can see this community has prospered a lot over all this time, compared to the other forums I frequent, some of which are getting more and more quiet.
So great job Ruud!

Although I don't have too much online time in the near future due to work commitments I hope I can contribute a little bit here or there.
Enough babbling. Here is my first contribution: a complete walkthrough & solution to this puzzle (including a text puzzle grid):
Code: Select all
.-----.--.--------.--.-----.
|19 |10|27 |6 |12 |
| .--: | .--. | :--. |
| |8 | | |13| | |16| |
:--: :--'--: :--'--: :--:
|15| |7 | |27 | |5 |
| | :-----: | | | |
| | |15 | | | | |
:--'--+-----'--'-----+--'--:
|6 |25 |14 |
:--.--+-----.--.-----+--.--:
|8 |18|14 |19|12 |13|13|
| | | | :-----: | |
| | | | |10 | | |
:--: :--.--: :--.--: :--:
|16| |11|23| | |6 | |17|
| '--: | '--' | :--' |
| | | | | |
'-----'--'--------'--'-----'
6/2 @ r12c7,r89c7={15|24} (NQ @ c7)
Innie-outies @ n3: r3c7-r4c89=6
=> r3c7=9, r4c89={12} (NP @ r4,n6) => r4c6<>9, r3c9=3|4
=> 16/3 @ r234c8: r23c8=14|15={68|78} (8 @ c8,n2 locked)
=> 14/2 @ r5c89 can't have 4 => 4 @ r6,c6 locked @ r6c89
=> 12/2 @ r6c67=[57|93], 10/2 @ r7c67=[28|37|46|73]
=> Innie-outies @ n9: r6c89=r7c7+4={34|46|47|48}
=> HP @ r6,n6: r5c89={59} => 6/2 @ r5c12={24} (NP @ r5,n4)
15/2 @ r34c1=[69|78|87], 15/2 @ r4c34={69|78}
r3c6+r4c67=27-9=18 must include at least 2 values from {678}
(Otherwise r3c6+r4c67 can't exceed 4+5+8=17)
r4c134 all from {6789} => Only one of r4c67 can be 6|7|8
=> r3c6=6|7|8 => r3c168={678} (NT @ r3)
=> Innie-outies @ n2: r4c5=r3c6-3=3|4|5
=> 13/3 @ r234c5: r2c5 must be from {6789}
(Otherwise r234c5 can't exceed 3+4+5=12)
7/2 @ r3c34={25} ({34} clashes r3c9) (NP @ r3)
Innie-outies @ n1: r3c3=r4c12-7 must be at least 7+3-7=3
=> r3c34=[52] => HS @ r6,n5: r6c5=2
=> r78c5=19-2=17={89} (NP @ c5,n8 )
Innies @ n8: r7c46=[14|32] => r7c67=[28|46] => r6c89={46|48}
=> 13/3 @ r678c8: r78c8=7|9 can't have 9, also can't have 7
(Otherwise r78c8={27} clashes r234c8={178|268})
=> Innies @ c8: r159c8=16 with 9 @ c8 locked
=> r159c8={259|349} ({169} clashes r234c8={178|268})
=> 7 @ c8 locked @ r23c8={78} (NP @ n3), r4c89=[12], r3c9=3
Innies @ n2: r23c5+r3c6=16 => r3c6=8, r234c5=[715], r3c2=4
=> r23c8=[87], r34c1=[69], r5c12=[42], r24c2=8-4=4=[13]
=> r4c67=27-8-9=10=[46] => r7c46=[32], r7c7=8, r6c89=[48]
=> r7c9=13-8=5 => r5c9=9, r15789c8=[25639], r12c7=[15]
=> r78c5=[98], r7c2=7 => 11/2 @ r89c3=[92]
All naked singles from here.
897543126
213976584
645218973
938754612
426831759
751629348
174392865
569487231
382165497

My fav sport
[Edited: minor typos fixed]
Posted: Fri Dec 28, 2007 11:34 pm
by Andrew
After finishing A2X I decided to have a go at A1V2, which I hadn't tried when Ed first posted it.
udosuk found a shorter solving route with a better version of step 4 and Ed's message gives a neat alternative finish.
I'll rate A1V2 as a solid 1.25. The two improvements mentioned above would make it a slightly easier 1.25.
Here is my walkthrough for A1V2.
Prelims
a) R12C3 = {19/28/37/46}, no 5
b) R12C7 = {15/24}
c) R3C34 = {16/25/34}, no 7,8,9
d) R34C1 = {69/78}
e) R34C9 = {14/23}
f) R4C34 = {69/78}
g) R5C12 = {15/24}
h) R5C89 = {59/68}
i) R67C1 = {17/26/35}, no 4,8,9
j) R6C67 = {39/48/57}, no 1,2,6
k) R67C9 = {49/58/67}, no 1,2,3
l) R7C67 = {19/28/37/46}, no 5
m) R89C3 = {29/38/47/56}, no 1
n) R89C7 = {15/24}
o) 19(3) cage in N1 = {289/379/469/478/568}, no 1
p) R234C2 = 1{25/34}, 1 locked for C2, clean-up: no 5 in R5C1
q) R678C5 = {289/379/469/478/568}, no 1
r) 27(4) cage at R3C6 = {3789/4689/5679}
s) 14(4) cage at R6C3 = {1238/1247/1256/1346/2345}, no 9
1. Naked quad {1245} in R1289C7, locked for C7, clean-up: no 7,8 in R6C6, no 6,8,9 in R7C7
2. 45 rule on C2 3 innies R159C2 = 19 = {289/469/478/568} (cannot be {379} because no 3,7,9 in R5C2), no 3
2a. R5C2 = {245} -> no 2,4,5 in R19C2
3. R678C2 = {279/369/378/567} (cannot be {459} which clashes with R234C2, cannot be {468} which clashes with R159C2), no 4
4. 45 rule on N3 2 innies R3C79 = 1 outie R4C8 + 11, max R3C79 = 13 -> max R4C8 = 2
4a. R3C79 = 12,13 = [84/93/94], clean-up: no 3,4 in R4C9
4b. R3C34 = {16/25} (cannot be {34} which clashes with R3C9)
[udosuk gave the better version 1 innie R3C7 = 2 outies R4C89 + 6 -> R3C7 = 9, R4C89 = {12}, locked for R4 and N6.]
5. Naked pair {12} in R4C89, locked for R4 and N6
6. 1 in 8(3) cage locked in R23C2, locked for C2, clean-up: no 9 in R12C3, no 6 in R3C4
6a. R234C2 = 1{25/34}
6b. 5 of {125} must be in R4C2 -> no 5 in R23C2
7. 4 in N6 locked in R6C89, locked for R6, clean-up: no 8 in R6C7
8. R234C8 = {69}1/{78}1/{59}2/{68}2, no 1,2,3,4 in R23C8
8a. Killer pair 8,9 in R3C7 and R23C8, locked for N3
9. 12(3) cage in N3 = {156/237/246} (cannot be {147} which clashes with R12C7, cannot be {345} which clashes with R3C9)
10. 27(4) cage at R3C6 = {3789/4689/5679}
10a. R4C67 cannot both be {6789} which would clash with R4C134 -> no 3,4,5 in R3C6
10b. 4,5 of {4689/5679} must be in R4C6 -> no 6 in R4C6
10c. Killer quad 6,7,8,9 in R4C134 and R4C67, locked for R4
11. Hidden killer quad 1,2,3,4 in R3C2, R3C34, R3C5 and R3C67 for R3 -> R3C5 = {1234}
12. R234C5 = {139/148/157/238/247/256/346}
12a. 6,7,8,9 only in R2C5 -> R2C5 = {6789}
13. 45 rule on N7 2 innies R7C13 = 1 outie R6C2, min R7C13 = 3 -> min R6C2 = 3
14. 45 rule on N9 2 innies R7C79 = 1 outie R6C8 + 9, max R7C79 = 17 -> max R6C8 = 8
15. 45 rule on N2 2 innies R3C46 = 1 outie R4C5 + 5, max R4C5 = 5 -> max R3C46 = 10, no 5 in R3C4, clean-up: no 2 in R3C3
15a. R89C3 = {29/38/47} (cannot be {56} which clashes with R3C3), no 5,6
16. 19(3) cage in N1 = {289/379/469/478} (cannot be {568} which clashes with R3C3), no 5
17. R3C3 = 5 (hidden single in N1), R3C4 = 2
18. 45 rule on N1 2 outies R4C12 = 12, no 6 in R4C1, clean-up: no 9 in R3C1
18a. 45 rule on R4, R4C12 = 12, R4C34 = 15, R4C89 = 3 -> R4C567 = 15 = {348/357/456}, no 9
18b. 9 in 27(4) cage locked in R3C67, locked for R3
19. R234C8 (step 8) = {78}1/{68}2/[961] (cannot be {59}2 because 5,9 only in R2C8), no 5
20. 45 rule on R12 3 innies R2C258 = 16, min R2C58 = 13 -> max R2C2 = 3
21. 45 rule on N2 3 remaining innies R2C5 + R3C56 = 16, min R2C5 + R3C6 = 13
-> max R3C5 = 3
22. 45 rule on C5 3 innies R159C5 = 13 = {148/157/238/247/256/346} (cannot be {139} which clashes with R3C5), no 9
23. 4 in N6 locked in R6C89
23a. 45 rule on N9 3 outies R7C6 + R6C89 = 14
23b. No 5 in R7C6 -> R6C89 cannot be 9, no 5 in R6C89, clean-up: no 8 in R7C9
24. 5 in N6 locked in R5C89 -> R5C89 = {59}, locked for R5 and N6, clean-up: no 1 in R5C1, no 3 in R6C6, no 4 in R7C9
24a. Naked pair {24} in R5C12 , locked for R5 and N4, clean-up: no 6 in R7C1
24b. No 9 in R6C9 -> max R6C89 = 12, no 1 in R7C6 (step 23a), clean-up: no 9 in R7C7
25. R234C2 (step 6a) = 1{25/34}
25a. 4 of {134} must be in R3C2 -> no 3 in R3C2
26. Killer pair 2,4 in R234C2 and R5C2, locked for C2
27. R3C7 = 9 (hidden single in C7)
28. R234C8 (step 19) = {78}1/{68}2, 8 locked for C8
29. R6C5 = 2 (hidden single in R6), R78C5 = 17 = {89}, locked for C5 and N8
30. R234C5 (step 12) = {157/346}
30a. 4 of {346} must be in R4C5 -> no 3 in R4C5
31. 4,5,9 in N2 locked in 27(5) cage = {14589/34569}, no 7
32. 45 rule on N8, 4 innies R7C456 + R8C5 = 22, R78C5 = 17 -> R7C46 = 5 = [14/32], clean-up: no 3,7 in R7C7
33. 3,7 in C7 locked in R456C7, locked for N6, clean-up: no 6 in R7C9
34. 14(4) cage at R6C3 = {1238/1256/1346} (cannot be cannot be {1247/2345} because 2,4 only in R7C3), no 7
34a. 2,4 only in R7C3 -> R7C3 = {24}
35. Naked pair {24} in R7C36, locked for R7, clean-up: no 6 in R6C1
36. Killer triple 2,3,4 in R12C3, R7C3 and R89C3, locked for C3
37. R678C8 = [436/463/472/634/652], no 1,9, no 5,7 in R8C8
38. Killer pair 6,7 in R23C8 and R678C8, locked for C8
39. 45 rule on C8 3 innies R159C8 = 16 = {259/349}, no 1
40. R4C8 = 1 (hidden single in C8), R4C9 = 2, R3C9 = 3, R3C5 = 1, R3C2 = 4, R24C2 = [13] (step 6a), R5C12 = [42], R24C5 = [75] (step 30), R6C67 = [93], clean-up: no 3 in R1C3, no 6 in R12C3, no 5 in R1C7, no 6 in R4C3, no 5 in R7C1
41. R4C6 = 4 (hidden single in R4), R7C67 = [28], R7C3 = 4, R7C4 = 3 (step 32), R78C5 = [98], clean-up: no 5 in R6C1, no 7 in R89C3, no 3 in R9C3
42. R6C34 = {16} (step 34), locked for R6 -> R67C1 = [71], R6C8 = 4, R6C9 = 8, R7C9 = 5, R5C89 = [59], R1C8 = 2, R9C8 = 9 (step 39), R6C2 = 5, clean-up: no 8 in R2C3, no 4 in R12C7 = [15], no 8 in R34C1 = [69], R4C3 = 8, R4C4 = 7, R4C7 = 6, R5C7 = 7, R3C6 = 8 (cage sum), R3C8 = 7, R78C8 = [63], R2C8 = 8, R7C2 = 7, R8C2 = 6 (cage sum)
and the rest is naked and hidden singles