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 Post subject: CNC 47 W X
PostPosted: Fri Oct 04, 2013 1:47 pm 
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Grand Master
Grand Master

Joined: Wed Apr 30, 2008 9:45 pm
Posts: 694
Location: Saudi Arabia
CNC 47 W X

Killer cages are nabmer: non-consecutive i.e. no consecutive entries within the cage.
Twin killer cages are remban groups so fully consecutive entries in any order.
It is Windoku.
It is X.
Plenty of work but probably not too hard.


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Sol:
198547632
234196875
756283914
379814256
621359487
485672391
543921768
912768543
867435129


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 Post subject: Re: CNC 47 W X
PostPosted: Sun Oct 06, 2013 10:54 pm 
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Grand Master
Grand Master

Joined: Wed Apr 23, 2008 6:04 pm
Posts: 1895
Location: Lethbridge, Alberta, Canada
Thanks HATMAN for another enjoyable puzzle. :)

Here is my walkthrough for CNC 47 WX:
This is a Windoku twin killer. Combinations in killer cages must use non-consecutive numbers, while the cages in HATMAN’s diagram with red borders use consecutive numbers (not necessarily in order).

The four windows are numbered W1, W2, W3 and W4; the hidden windows will give their cells, for example hidden window R159C159.

Prelims
a) 10(3) killer cage at R1C1 = {136} (only possible combination, other combinations contain consecutive numbers)
b) 18(3) killer cage at R1C9 = {279/369/468} (other combinations contain consecutive numbers), no 1,5
c) 12(3) killer cage at R7C3 = {138/147/246} (other combinations contain consecutive numbers), no 5,9
d) 20(3) killer cage at R7C7 = {479} (only possible combination, other combinations contain consecutive numbers)

Steps resulting from Prelims
1a. Naked triple {136} in 10(3) cage at R1C1, locked for N1 and D\
1b. Naked triple {479} in 20(3) cage at R7C7, locked for N9 and D/

2. 5 on both diagonals only in N5 -> R5C5 = 5
2a. Naked pair {28} in R4C4 + R6C6, locked for N5

3. 18(3) killer cage at R1C9 = {279/369} (cannot be {468} which clashes with 12(3) killer cage at R7C3), no 4,8, 9 locked for N3 and D/
3a. 12(3) killer cage at R7C3 = {138/147} (cannot be {246} which clashes with 18(3) killer cage), no 2,6, 1 locked for N7 and D/
3b. Killer pair 3,7 in 18(3) killer cage and 12(3) killer cage, locked for D/
3c. Naked pair {46} in R4C6 + R6C4, locked for D/ and N5
3d. 18(3) killer cage = {279} (only remaining combination), locked for N3
3e. 12(3) killer cage = {138} (only remaining combination), locked for N7

4. R2C2 + R3C3 = {136} -> Remban group R23C23 = {1234/3456} (other combinations only contain one of 1,3,6), 3,4 locked for N1 and W1

5. Remban group R4C234 = {678/789} -> R4C4 = 8, placed for W1, R4C23 = {67/79}, 7 locked for R4, N4 and W1
5a. R6C6 = 2, placed for W4

6. R7C3 + R8C2 = {138} -> Remban group R78C78 = {1234}, locked for N7 and W3 -> R6C4 = 6, R4C6 = 4, placed for W2
6a. R9C1 = 8, placed for hidden window R159C159
6b. 7 in W3 only in R78C4, locked for C4 and N8
6c. 8 in W3 only in R6C23, locked for R6 and N4
6d. 3,4 in C1 only in R456C1, locked for N4
6b. 8 in N1 only in R1C23, locked for R1

7. R7C7 + R8C8 = {479} -> Remban group R78C78 = {4567/6789} (other combinations only contain one of 4,7,9), 6,7 locked for N9 and W4

8. Remban group R23C23 (step 4) = {3456} (cannot be {1234}, locked for W1 because R23C4 = {59} clashes with R78C4, ALS block), locked for N1 and W1 -> R1C1 = 1, placed for hidden window R159C159
8a. Naked pair {79} in R4C23, locked for R4, N4 and W1
8b. Naked pair {12} in R23C4, locked for C4 and N4
8c. Naked pair {58} in R6C23, locked for R6, N4 and W3
8d. Naked pair {79} in R78C4, locked for C4 and N8 -> R5C4 = 3, R4C5 = 1, placed for hidden window R234C159
8e. 1 in N4 only in R5C23, locked for R5
8f. 5 in C1 only in R78C1, locked for N7

9. 5 in hidden window R234C159 only in R234C9, locked for C9

10. 3 in hidden window R159C159 only in R19C5, locked for C5

[It’s getting a bit harder now. At first I analysed the Remban group at R1C6, but I’ve left that until a bit later after finding the next step …]

11. Consider placements for R9C4
11a. R9C4 = 4 => R9C9 = 9, R7C7 + R8C8 = {47} => Remban group R78C78 = {4567}, locked for N9 => R9C6 = 5 (hidden single in R9)
or R9C4 = 5
-> 5 must be in R9C46, locked for R9 and N8
11b. 5 in N9 only in Remban group R78C78 = {4567}, locked for N9 and W4 -> R9C9 = 9

12. Naked pair {67} in R9C23, locked for N7 and hidden window R159C234, no 7 in R1C23, no 6 in R5C23
12a. Naked pair {59} in R78C1, locked for C1
12b. Naked pair {27} in R23C1, locked for C1, N1 and hidden window R234C159, no 7 in R23C5
12c. Naked pair {89} in R1C23, locked for R1

13. R1C9 = 2 (hidden single in R1), placed for hidden window R159C159
13a. Naked pair {79} in R2C8 + R3C7, locked for W2
13b. 9 in N2 only in R23C5, locked for C5 -> R6C5 = 7, R5C6 = 9

14. R1C6 = 7 (hidden single in N2) -> Remban group at R1C6 = [789], R2C7 = 8, placed for W2, R3C7 = 9
14a. R23C5 = [98] (hidden pair in N2)

and the rest is naked singles, with using the windows.

Rating Comment:
I'll rate my walkthrough for CNC 47 WX at Easy 1.5. I used hidden windows and a short forcing chain.


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