## Solving Ex 173 with Dead End Chain DEC

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Jens
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Joined: Sunday 25. July 2010, 14:55
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### Solving Ex 173 with Dead End Chain DEC

Ex 173
The solver gets A6=5c, B9=8c, A3=7c, A1=2, B1=3c, J2=8c, H9=5, J9=4c, E6=7 and H1=8c.
It goes on with C5=3s, D678=789, BCEFJ12345=Star(5)Fish5, D1-4=1-4, D1=4, CDFH4678=JF7, B8=9c, E8=2, E9=1c, F8=3, J8=6, F9=2c, H8=7, J5=5, D8=8, C8=4c, D7=7, D6=9c, 345CFG=SF8, C7=6c, G2-8=2-8, G7=2, H7=1c, 24FH=XW9, H5=6, B5=2, B4=5, J6=1s, J4=2c, D4=1s and DE23=XW3 or 46GH=XW3.
Str8ts Ex173 #44+.png (11.91 KiB) Viewed 22483 times
Begin and end of AIC (Alternating Infering Chain) /C4//C6//H6//H4//G4/ can see each other in column 4. Starting and ending with 8 will give /C4~8//C6~7//H6~2//H4~3//G4~8/. This brings a contradiction in column 4.
Now I declare a new DEC (Dead End Chain) which is based on this contradiction. Red marked contradicting digits 8 can be removed from DEC head cells. The green marked digits will stay alone.
C4=7, G4=3, C6=2, H4=9, C2=5, F4=8c, H2=2, H6=3c, C3=8c, D2=3, F5=4, D3=2c, E2=6, G3=6, G5=8c, B2=4, E1=5, F2=9c, F3=5, G6=4c, B6=6c, E3=3c, F1=6c and F6=7.
Str8ts Ex173 #68.png (23.07 KiB) Viewed 22483 times
Gruß von Jens