Assassin 79 RP

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Ruud
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Assassin 79 RP

Post by Ruud »

By now, you should know what RP means. If not, there will surely be a friendly forum member who can explain this to you.

Image

3x3::k:7424:2561:2561:2561:4868:4868:4614:4614:4614:7424:7424:4619:4619:4619:4868:4868:4112:4614:2578:7424:2068:2068:3350:3350:4112:4112:4890:2578:2578:2578:5918:5918:3350:4129:4129:4890:3876:5925:2854:2854:5918:2345:2345:4129:4890:3876:5925:5925:2864:5918:5918:4659:4659:4659:3876:5431:5431:2864:2864:2107:2107:4157:4659:3647:5431:5185:5185:5699:5699:5699:4157:4157:3647:3647:3647:5185:5185:4685:4685:4685:4157:

It is not unsolvable. That's all I want to add...

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
gary w
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rp

Post by gary w »

OK,so what does it mean??

Really problematic?
Ruud's pulitzer prize puzzle?

Gary
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RP

Post by sublue »

I'm going to guess that RP means Rejected Puzzle. Probably because it is Hard with a capital H. But I'm a Rookie, so I could be wrong about that.
Susan
Para
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Post by Para »

Hi

Actually it is Rejected Pattern. Ruud intended to make an assassin with this pattern but couldn't get the difficulty spot on with this pattern so he changed it a little: he split the two S-shaped tetris pieces in the left top and right bottom corner in two 2 cell cages. I suspected it to be either those cage or the L-shaped pieces in the right top and left bottom corner.

Earlier mentions:
- Assassin 60 - Rejected Pattern
- Assassin 43 V0

greetings

Para
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Post by Para »

Hi all

This RP doesn't match up with the 60RP or even 60RP-lite. It is fun to solve. The opening is very friendly, but needed some nice moves towards the end.

Walk-through A79-RP

1. 10(3) at R1C2 = {127/136/145/235}: no 8,9

2. R3C34 and R7C67 = {17/26/35}: no 4,8,9

3. 19(3) at R3C9 = {289/379/469/478/568}: no 1

4. R5C34 = {29/38/47/56}: no 1

5. R5C67 = {18/27/36/45}: no 9

6. 11(3) at R6C4 = {128/137/146/236/245}: no 9

7. 21(3) at R7C2 = {489/579/678}: no 1,2,3

8. 14(4) at R8C1 = {1238/1247/1256/1346/2345}: no 9

9. 22(3) at R8C5 = {589/679}: no 1,2,3,4; 9 locked for R8

10. 29(4) at R1C1 = {5789} -> locked for N1
10a. Clean up: R3C4: no 1,3

11. 10(4) at R3C1 = {1234}: pointing -> R56C1: no 1,2,3,4

12. 23(3) at R5C2 = {689} -> locked for N4
12a. 15(3) at R5C1 = {57}[3]: R7C1 = 3; R56C1 = {57} -> locked for C1 and N4
12b. R12C1 = {89} -> locked for C1 and N1
12c. R23C2 = {57} -> locked for C2
12d. 6 in C1 locked for N7
12e. Clean up: R5C4: no 2,3,4,5,6

13. 45 on N7: 1 innie: R8C3 = 7
13a. 21(3) at R7C2 = {489}(last combo) -> locked for N7; 9 locked for R7
13b. R9C3 = 5(hidden)
13c. 22(3) at R8C5 = {589}(last combo) -> locked for R8
13d. R8C2 = 4
13e. R7C23 = {89} -> locked for R7
13f. R567C2 = {689} -> locked for C2
13g. Clean up: R7C67: no 5

14. 45 on R89: 1 outie: R7C8 = 4

15. 1 in N4 locked for R4 and 10(4) at R3C1
15a. 3 in 10(4) at R3C1 -> locked for R4 and N4
15b. Clean up: R5C4: no 6
15c. R5C67 = {18/36/45}: {27} blocked by R5C34: no 2,7

16. 45 on R789: 1 innie and 1 outie: R6C4 + 2 = R7C9: R6C4 = {345}; R7C9 = {567}
16a. 11(3) at R6C4 = [3]{17/26}/[4]{25}: [4]{16} blocked by R7C67: R6C4: no 5
16b. Clean up: R7C9: no 7

17. 45 on R12: 1 innie and 1 outie: R2C8 + 4 = R3C2: R2C8 = {13}
17a. 16(3) at R2C8 = [1]{69/78}/[3]{49/58/67}: R3C78: no 1,2,3

18. 45 on N689: 3 outies: R3C9 + R5C6 + R6C4 = 15: Max R3C9 + R6C4 = 12 -> Min R5C6 = 3: no 1; Min R5C6 + R6C4 = 7 -> Max R3C9 = 8: no 9; Max R5C6 + R6C4 = 12 -> Min R3C9 = 3: no 2
18a. Clean up: R5C7: no 8

19. 13(3) at R3C5 = {13}[9]/{148/157/238/247/256/346}: R3C56: no 9

20. 9 in R3 locked for N3
20a. 9 in R3 locked within 16(3) at R2C8 -> 16(3) = [1]{69}/[3]{49}: no 5,7,8; R3C78 = [49]/{69} = {4|6..}
20b. R3C34 = [17/35]: {26} blocked by R3C1 + R3C78: no 2,6
20c. R3C24 = {57} -> locked for R3

21. 18(3) at R2C3 = {279/369/378/459/468}={8|9..}: {189} blocked by R2C1; {567} blocked by R2C2: no 1
21a. Killer Pair {89} in R2C1 + 18(3) at R2C3 -> locked for R2

22. 45 on N3: 2 innies: R2C7 + R3C9 = 11 = [38/56/74]: R2C7 = {357}; R3C9: no 3

23. 45 on C123: 3 outies and 1 innie: R135C4 + 13 = R2C3 = R135C4 = 15/16/17/19 = [159/357/259/457/179/359/379]: R1C4 = {1234}
23a. 10(3) at R1C2 = {1[6]3}(last combo) -> locked for R1; R1C3 = 6
23b. Naked Pair {13} in R1C2 + R3C3 -> locked for N1
23c. Naked Pair {24} in R25C3 -> locked for C3

24. Hidden Killer Pair {13} in R3C3 + R3C56: R3C56 needs one of {13}
24a. Killer Pair {13} in R1C4 + R3C56 -> locked for N2
24b. 13(3) at R3C5 = {148/238/346}: no 5,7,9

25. 18(4) at R1C7 = {1278/2358/2457}:{1368/1458/1467/2367/3456} blocked by 16(3) at R2C8: no 6
25a. 6 in N3 locked for R3
25b. 18(3) at R2C3 = [2]{79}/[4]{59}/[4]{68}: R2C45 = {59/68/79}= {5|6|7..}: no 2,4

26. Hidden Killer Triple {567} in R3C4 + R2C45 + (R1C56 + R2C6): R1C56 + R2C6 needs one of {567}
26a. 19(4) at R1C5 = {259}[3]/{268}[3]/{246}[7]: {248}[5]/{457}[3] blocked: R1C56 + R2C6 = {259/268/246}: no 7; 2 locked for N2; R2C7: no 5
26b. Clean up: R3C9: no 6

27. 6 in R3 locked within 16(3) at R2C8 -> 16(3) = [1]{69}; R2C8 = 1
27a. R3C2 = 5(step 17); R3C34 = [17]; R1C24 = [31]; R2C27 = [73]; R5C34 = [29]; R4C123 = [413]
27b. R3C1 = 2; R2C3 = 4; R9C2 = 2; R3C9 = 8(step 22)

28. 13(3) at R3C5 = {34}[6]: R4C6 = 6; R3C56 = {34} -> locked for N2
28a. 19(4) at R1C5 = 3{259}(last combo): {259} -> locked for N2; 9 locked for R1
28b. R12C1 = [89]
28c. Clean up: R7C7: no 2

29. 19(3) at R3C9 = 8[74]: 8[56] blocked by R7C9: R45C9 = [74]
29a. R1C7 = 4(hidden); R1C8 = 7(hidden)
29b. Naked Pair {25} in R12C9 -> locked for C9
29c. R7C9 = 6; R6C4 = 4(step 16); R8C8 = 2(hidden); R6C2 = 6(hidden)
29d. R5C2 = 8; R6C3 = 9; R7C23 = [98]; R9C9 = 9(hidden); R8C9 = 1

And the rest is naked and hidden singles.

greetings

Para
Last edited by Para on Thu Apr 17, 2008 2:08 pm, edited 1 time in total.
Afmob
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Post by Afmob »

This one started quite promising with some early placements but after that there were only little eliminations you could do. But if you find the right moves it doesn't take too long to solve.

A79 RP Walkthrough:

1. C123
a) 29(4) = {5789} locked for N1
b) 23(3) = {689} locked for N4
c) 10(4) = {1234} locked between C1 and N4 -> R56C1 <> 1,2,3,4
d) 15(3) = {357} -> R7C1 = 3, {57} locked for C1+N4
e) Innies N7 = 10(2) = [37] -> R8C3 = 7
f) 21(3) = {489} locked for N7
g) 10(4) = {1234} -> 3 locked for R4+N4
h) 29(4) = {5789} -> R23C2 = {57} locked for C2
i) 14(4) = {1256} -> R9C3 = 5
j) 8(2): R3C4 <> 1,3
k) 11(2) = [29/47]

2. R789
a) 22(3) = {589} locked for R8
b) Innies+Outies R89: R8C2 = R7C8 = 4
c) 21(3) = {489} -> 8,9 locked for R7
d) 8(2) = {17/26}
e) 11(3): R6C4 <> 5 because R7C45 <> 4
f) Innies+Outies R789: -2 = R6C4 - R7C9
-> R7C9 = (56), R6C4 = (34)
g) 16(4) = 4{129/138/237}
h) 16(4) must have 7,8 xor 9 and it's only possible @ R9C9 -> R9C9 = (789)

3. R45
a) 1 locked in 10(4) for R4; R3C1 <> 1
b) Killer pair (27) of 11(2) blocks {27} of 9(2)
c) 19(3) <> 5 because {568} blocked by R7C9 = (56)

4. R123
a) Innies+Outies R12: 4 = R3C2 - R2C8
-> R2C8 = (13)
b) 16(3): R3C78 <> 1,2,3 because R2C8 <= 3
c) Innies N3 = 11(2) -> R2C7 <> 1,6
d) 10(3): R1C4 <> 2,4 because R1C23 <> 5,7
e) 13(3): R3C56 <> 9 because R4C6 <> 1,3
f) 9 locked in R3C789 for N3
g) Innies N3 = 11(2): R3C9 <> 2

5. N36
a) Innies+Outies: -3 = R7C9 - R25C7; R7C9 = (56)
-> R5C7 <> 8 because R2C9 >= 2
b) 9(2): R5C6 <> 1

6. C123
a) Hidden pair (89) in R67C3 for C3 -> R6C3 <> 6
b) 6 locked in R56C2 for C2
c) 18(3) <> 1 because {189} blocked by R2C1 = (89)
d) 18(3): R2C45 <> 2 because R2C3 <= 6

7. N3689 !
a) ! Outies N689 = 15(2+1): R3C9 <> 9 because R5C6+R6C4 >= 7
b) 9 locked in 16(3) @ N3 = 9{16/34}
c) Innies N3 = 11(2) <> 2
d) 2 locked in 18(4) @ N3 = 2{178/358/367/457}
e) 18(4) @ N3 <> 6 because {2367} blocked by Killer pair (36) of 16(3) @ N3

8. R123
a) 6 locked in R3C789 for R3
b) 8(2) <> 2
c) Naked pair (57) locked in R3C24 for R3
d) 10(3): R1C4 <> 6 because R3C3 = (13) blocks {136}
e) Innies N3 = 11(2): R2C7 <> 4

9. N1234 !
a) Outies N124 = 18(2+1): R2C7 <> 8 since R5C4+R4C6 can't be 10(2) because R4C6 <> 1,3
b) Innies N3: R3C9 <> 3
c) 19(3) <> 3 because R3C9 = (468)
d) ! Innies+Outies N14: 13 = R135C4 - R2C3
-> R1C4 <> 5,7 because R135C4 would be 21 but R2C3 <= 6
e) 10(3) = {136} -> R1C3 = 6; {13} locked for R1
f) Naked pair (13) locked in R1C2+R3C3 for N1
g) 18(3) = {279/459/468} because R2C3 = (24) -> R2C45 <> 3,4
h) 1,3 locked in R2C789 for R2

10. N23 !
a) 1,3 only possible @ R1C4 + 13(3) for N2 -> 13(3) must have 1 xor 3
-> 13(3) = {148/238/346}, {157} impossible because R3C56 <> 5,7
b) ! 19(4): R2C7 <> 5 because R1C56+R2C6 <> 3 and R1C56+R2C6 = {248}
would leave no combo for 13(3)
c) Killer pair (37) locked in 18(4)+R2C7 for N3
d) 16(3) = {169} -> R2C8 = 1, {69} locked for N3

11. R123
a) Outies R12 = 20(3) = {569} -> R3C2 = 5
b) R2C2 = 7, R3C4 = 7 -> R3C3 = 1
c) 18(3) = 4{59/68} -> R2C3 = 4
d) R2C7 = 3
e) 18(4) = {2457} locked for N3
f) R3C9 = 8, R5C3 = 2, R5C4 = 9
g) 19(3) = {478}, {47} locked for C9+N6

12. N89
a) 16(4) = {1249} -> R9C9 = 9, R8C8 = 2, R8C9 = 1
b) 18(3) = 8{37/46} -> 8 locked for R9
c) 20(4) = {3467}, {346} locked for N8
d) 18(3) = {378} -> R9C8 = 3
e) Hidden Single: R8C4 = 3 @ N8
f) 11(3) = {245}, R6C4 = 4, {25} locked for R7+N8
g) Hidden Single: R6C9 = 3 @ C9
h) 18(4) = {1368} -> R7C9 = 6, R6C8 = 8, R6C7 = 1

13. Rest is singles.

Estimated rating: 1.5, it had some tricky moves but compared to M2 it's easier.
Last edited by Afmob on Wed Dec 12, 2007 12:44 pm, edited 4 times in total.
gary w
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Post by gary w »

Yes,this was a nice one.As Para and Afmob note



Early placements of r7c1=3 r8c2=4 r9c3=5 r7c8=4 fairly straightforward.
After that I used the I-O of N1245 (also used in V1) together with the restrictions imposed by the 10(4) cage N14 and combos in r3 to show that r2c7 could only be 3.This rapidly led to a solution.



So although my solving path was quite short it was difficult to see and the puzzle took me a while to solve.Like Afmob,based on other killers I'ld rate it approx. 1.5.

Regards

Gary
Andrew
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Post by Andrew »

As Para has said, this differs from A79 by having Tetris pieces in N1 and N9 which became two 2-cell cages in A79. The Tetris piece in N1 very quickly becomes two 2-cell cages; however the same doesn't happen in N9 making it harder than A79.

I finished this puzzle last week but have only just gone through Para's and Afmob's walkthroughs. They both used outies from N689 which I remember looking at but probably too early and never returned to them later. As a result my solution path was rather different.

I found the main challenge was to spot some moves, rather than actual difficulty of the moves.

Afmob rated this puzzle at 1.5, saying that it was easier than Maverick 2. I haven't yet tried that puzzle so I'll say that A79RP was easier than Maverick 1 and rate A79RP at 1.5.

Here is my walkthrough for A79RP

Prelims

a) R3C34 = {17/26/35}, no 4,8,9
b) R5C34 = {29/38/47/56}, no 1
c) R5C67 = {18/27/36/45}, no 9
d) R7C67 = {17/26/35}, no 4,8,9
e) R1C234 = {127/136/145/235}, no 8,9
f) R345C9 = {289/379/469/478/568}, no 1
g) 23(3) cage in N4 = {689}, locked for N4, clean-up: no 2,3,5 in R5C4
h) 11(3) cage at R6C4 = {128/137/146/236/245}, no 9
i) 21(3) cage in N7 = {489/579/678}, no 1,2,3
j) R8C567 = 9{58/67}, 9 locked for R8
k) 29(4) cage in N1 = {5789}, locked for N1, clean-up: no 1,3 in R3C4
l) 10(4) cage at R3C1 = {1234}, CPE no 1,2,3,4 in R56C1
m) 14(4) cage in N7 = {1238/1247/1256/1346/2345}, no 9

1. Naked pair {57} in R56C1, locked for C1 and N4, R7C1 = 3, clean-up: no 4,6 in R5C4, no 5 in R7C67
1a. Naked pair {89} in R12C1, locked for C1 and N1
1b. Naked pair {57} in R23C2, locked for C2

2. 1 in N4 locked in R4C123, locked for R4 and 10(4) cage -> no 1 in R3C1
2a. 6 in C1 locked in R89C1, locked for N7
2b. 3 in 10(4) cage locked in R4C23, locked for R4 and N4, clean-up: no 8 in R5C4
2c. R5C67 = {18/36/45} (cannot be {27} which clashes with R5C34)

3. 14(4) cage in N7 = {1256} (only remaining combination with 6 in R89C1) -> R9C3 = 5, 1,2 locked for N7
3a. 4 in C1 locked in R34C1, locked for 10(4) cage -> no 4 in R4C23

4. 21(3) cage in N7 = {489}, (only remaining combination), locked for N7 -> R8C3 = 7
4a. 9 in N7 locked in R7C23, locked for R7

5. R8C567 = {589} (only remaining combination), locked for R8 -> R8C2 = 4
5a. Naked pair {89} in R7C23, locked for R7

6. 45 rule on R89 1 remaining outie R7C8 = 4
6a. 16(4) cage at R7C8 = {1249/1348/2347}, no 6
6b. 7,8,9 only in R9C9 -> R9C9 = {789}

7. 45 rule on R12 1 outie R3C2 = 1 innie R2C8 + 4, R2C8 = {13}
7a. Max R2C8 = 3 -> min R3C78 = 13, no 1,2,3

8. Hidden pair {89} in R67C3, no 6
8a. 6 in N4 locked in R56C2, locked for C2

9. 45 rule on N3 2 innies R2C7 + R3C9 = 11 = {29/38/47/56}, no 1

10. 45 rule on N89 1 remaining innie R7C9 = 1 outie R6C4 + 2, R7C9 = {567}, R6C4 = {345}

11. 45 rule on N89 3 innies R7C459 = 13 = {157/256}
11a. {157} must be {17}5 (cannot be {15}7 which would make 11(3) cage 5{15})
11c. {256} = {25}6/{26}5
11d. -> no 7 in R7C9, no 5 in R6C4 (step 10)

12. 45 rule on R123 2 innies R3C19 = 1 outie R4C6 + 4, no 1,3 in R4C6 -> no 3 in R3C9, clean-up: no 8 in R2C7 (step 9)

13. R1C234 = {127/136/145/235}
13a. 5,7 of {127/235} must be in R1C4 -> no 2 in R1C4
13b. 5 of {145} must be in R1C4 -> no 4 in R1C4

14. R2C345 = {279/369/378/459/468} (cannot be {189} which clashes with R2C1, cannot be {567} which clashes with R2C2), no 1
14a. 2 of {279} must be in R2C3 -> no 2 in R2C45

15. Killer pair 8,9 in R2C1 and R2C345, locked for R2, clean-up: no 2 in R3C9 (step 9)

16. 45 rule on N5 4 innies R45C6 + R56C4 = 22 = {1489/2389/3469/3478/4567} (cannot be {1579/1678/2569/2578} because R6C4 only contains 3,4, cannot be {2479} because 2,7,9 only in R4C6 + R5C4, cannot be {3568} because R5C4 only contains 7,9)
16a. 7,9 must be in R5C4 -> no 7,9 in R4C6
16b. 23(5) cage in N5 must contain 2/4, 6/8 and 7/9

17. R3C19 = R4C6 + 4 (step 12), no 7,9 in R4C6 -> no 9 in R3C9, clean-up: no 2 in R2C7 (step 9)

18. 45 rule on R1 3 outies R2C679 = 1 innie R1C1 + 2
18a. R1C1 = {89} -> R2C679 = {127/145/146/235/236/245} (cannot be {136/137} which clash with R2C8)
18b. 7 of {127} must be in R2C7 -> no 7 in R2C69

19. 45 rule on N36 2 innies R25C7 = 1 outie R7C9 + 3, max R7C9 = 6 -> max R25C7 = 9, no 8 in R5C7, clean-up: no 1 in R5C6

20. 1 in N5 locked in 23(5) cage = {12389/12569/12578/14567} (cannot be {12479} which clashes with R5C4, cannot be {13469/13478} which clash with R6C4, cannot be {13568} because must contain 7/9)

21. 18(4) cage at R6C7 = {1269/1359/1368/1458/1467/2358/2367/2457} (cannot be {1278/2349} because R7C9 only contains 5,6, cannot be {3456} which clashes with R6C4)
21a. R7C9 = {56} -> no 5,6 in R6C789
21b. R7C9 = R6C4 + 2 (step 10) -> 18(4) cage cannot contain {35} or {46} eliminating {1359/1467}
21c. -> 18(4) cage = {1269/1368/1458/2358/2367/2457}
21d. Hidden killer quad 1,2,3,4 in R6C4, R6C56 and R6C789 for R6 -> R6C56 must contain one of 1,2,3,4

22. 13(3) cage at R3C5 = {148/157/238/247/256/346} (cannot be {139} because no 1,3,9 in R4C6), no 9

23. 9 in R3 locked in R3C78, locked for N3
23a. 16(3) cage in N3 = 1{69}/[349], no 5,7,8
23b. If [349] -> R3C1 = 2
23c. R3C34 cannot be {26} (steps 23a and 23b) = [17/35]
23d. Naked pair {57} in R3C24, locked for R3, clean-up: no 4,6 in R2C7 (step 9)

24. Hidden killer pair 1,3 in R3C3 and R3C56 for R3 -> R3C56 must contain 1/3
24a. 13(3) cage at R3C5 (step 22) = {148/238/346} (cannot be {256} because no 1,3), no 5

25. R345C9 = {289/469/478} (cannot be {379} because R3C9 only contains 4,6,8, cannot be {568} which clashes with R7C9), no 3,5
25a. If {478} -> R9C9 = 9
25b. -> no 9 in R6C9

26. 45 rule on N6 2 outies R37C9 = 1 innie R5C7 + 8
26a. R37C9 cannot total 12 -> no 4 in R5C7, clean-up: no 5 in R5C6

27. 5 in N5 locked in 23(5) cage (step 20) = {12569/12578/14567}, no 3

28. Hidden killer triple 7,8,9 in 16(3) cage, R45C9 and R6C789 for N6 -> each must contain one of 7,8,9
28a. 8 of {289/478} in R345C9 must be in R3C9 -> no 8 in R45C9
28b. 16(3) cage = {169/259/268/358/367/457} (cannot be {178} which contains 7,8, cannot be {349} which clashes with R45C9)

29. 2 in N3 locked in 18(4) cage = {1278/2358/2457} (cannot be {2367} which clashes with 16(3) cage), no 6
29a. 6 in N3 locked in R3C789, locked for R3

30. R2C2 = {57}, R2C7 = {357} -> R2C345 cannot contain more than one of 3,5,7
30a. R2C345 (step 14) = {279/369/459/468} (cannot be {378} which contains 3 and 7)

31. 7 in N3 in R1C789 or R2C7, CPE no 7 in R1C56
31a. If 7 in R2C7 => R2C679 = {127} => R1C1 = 8 (step 18a) clashes with 18(4) cage (step 29)
31b. -> no 7 in R2C7, clean-up: no 4 in R3C9 (step 9)
31c. 18(4) cage in N3 (step 29) = {1278/2457}, no 3, 7 locked for R1
31d. 3 in N3 locked in R2C78, locked for R2

32. R345C9 (step 25) = {289/469/478}
32a. 6 of {469} must be in R3C9 -> no 6 in R45C9

33. R2C345 (step 30a) = {279/459/468}
33a. Hidden killer pair 2,4 in R2C345 and R2C679 for R2 -> R2C679 must contain one of 2,4
33b. R2C679 (step 18a) = {145/235/236} (cannot be {146} because R2C7 only contains 3,5, cannot be {245} which contains 2 and 4)

34. R25C7 = R7C9 + 3 (step 19), min R7C9 = 5 -> min R25C7 = 8, no 1 in R5C7, clean-up: no 8 in R5C6
[I missed R25C7 = {35/36}, 3 locked in R25C7 for C7. Didn’t make much difference, R2C7 was fixed in step 36b.]

35. R45C6 + R56C4 (step 16) = {3469/3478} (cannot be {2389} because 2,8 only in R4C6), no 2, 4 locked for N5

36. 19(4) cage at R1C5 = {1369/1459/2359/2368/2458} (cannot be {1468} because R2C7 only contains 3,5)
36a. Killer pair 8,9 in R1C1 and R1C56, locked for R1, clean-up: no 1 in 18(4) cage in N3 (step 31c)
36b. 18(4) cage in N3 = {2457}, locked for N3 -> R2C78 = [31], clean-up: no 6 in R5C6

37. R3C9 = 8 (hidden single in N3), R45C9 = {29/47} (step 32)
37a. Killer pair 7,9 in R45C9 and R9C9, locked for C9

38. R7C9 = 6 (hidden single in C9), R6C4 = 4 (step 10), R5C67 = [36], R3C78 = [96], clean-up: no 2 in R7C67
38a. Naked pair {17} in R7C67, locked for R7
38b. Naked pair {25} in R7C45, locked for N8
38c. Naked pair {89) in R8C56, locked for R8 and N8 -> R8C7 = 5

39. 20(4) cage at R8C3 = {3467} (only remaining combination) -> R9C5 = 4
39a. Naked pair {36) in R89C4, locked for C4 and N8
39a. Naked pair {17} in R79C6, locked for C6

40. R1C4 = 1 (hidden single in C4), R1C23 = [36], R3C34 = [17], R23C2 = [75], R5C34 = [29], R2C3 = 4, R3C1 = 2, R3C56 = [34], R4C6 = 6 (step 24a), R4C123 = [413], R9C2 = 2, R5C2 = 8, R6C23 = [69], R7C23 = [98], clean-up: no 2,9 in R4C9, no 7 in R5C9 (both step 37) -> R45C9 = [74], R9C9 = 9, R5C8 = 5, R56C1 = [75], R5C5 = 1

41. Naked pair {25} in R12C9, locked for C9 and N3 -> R1C78 = [47]

42. Naked pair {25} in R2C69, locked for R2 -> R2C4 = 8, R12C1 = [89], R2C5 = 6

43. R8C8 = 2 (hidden single in R8), R4C8 = 9 (hidden single in C8)

44. R8C9 = 1 (cage sum)

and the rest is naked singles
mhparker
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Post by mhparker »

Hi Andrew,

Thanks for the WT.
Andrew wrote:I found the main challenge was to spot some moves, rather than actual difficulty of the moves.
It would be interesting to know which moves you found difficult to spot. I suspect your step 24 is one of them. I think everybody required some variation on that theme to complete the puzzle.

I also like Afmob's approach of preceding key moves with a !, which enables me to home in on the interesting bits even if not following the WT step-by-step. The latter isn't always necessary, because the solution paths are often narrow enough to be able to run an automated solver to a grid state which is a close enough approximation to the actual one such that the move in question is still valid. This can save a lot of time.

Incidentally, I went quite a long way towards doing my own WT for the A79RP. However, before starting the mop-up phase, I took a peek at Para's WT to see whether my WT would be sufficiently different to warrant publishing it. Needless to say, it wasn't. So I didn't.
Cheers,
Mike
Andrew
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Post by Andrew »

mhparker wrote:It would be interesting to know which moves you found difficult to spot. I suspect your step 24 is one of them. I think everybody required some variation on that theme to complete the puzzle.
It was several days between when I completed the puzzle and when I checked it and worked through the other posted WTs so I can't be sure which were the more difficult ones to spot.

I've been getting better at hidden killers in recent weeks (I'd been using them before but not knowing they were called that) so step 24 came fairly easily. All the posted WTs used it so it was clearly key to the solution although I didn't realise that at the time.

Glancing at my WT I would think that step 28 was harder. Also I seem to remember N3 being hard so I think I found step 29 difficult to spot even though it isn't a hard move.
mhparker wrote:I also like Afmob's approach of preceding key moves with a !, ...
I agree with you. Afmob's !s add interest to his WTs.

My WTs are, at best, semi-optimised in that I now insert steps that I ought to have spotted earlier but don't deliberately attempt to optimise them. Therefore I'm unlikely to use ! in my WTs. However I can well imagine that Mike's comment may encourage some others to start doing it.
mhparker
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Location: Germany

Post by mhparker »

Hi Andrew,
Andrew wrote:My WTs are, at best, semi-optimised... Therefore I'm unlikely to use ! in my WTs.
I don't think use of ! has anything to do with optimization per se, has it? Could you clarify that, please?

BTW, I wasn't suggesting that we all start using this notation (although I find it a great idea and may start using it myself).

Like you, I often optimize my WTs if I see a move that I missed earlier, and if I don't have to unwind the WT very far in order to correct it. If I missed the move near the beginning (as was the case just recently with my A2 WT), I have to consider whether I really want to essentially do the whole puzzle again, or instead simply add a comment relating to the missed move.
Cheers,
Mike
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