The New Sudoku Players' Forum

[Wolfgang]

My friend loves Angus' advanced puzzles, because she knows that they are difficult, but solvable in an enjoyable way. But is that true also for the pack 2 ? Both for puzzle001 and puzzle002 she needed forcing chains.
This is, where she got stuck with puzzle002:

Code: Select all

|7..|42.|163|
|.43|51.|2..|
|.1.|.3.|594|
-------------
|..7|6.4|321|
|.3.|19.|.46|
|164|3.2|9.5|
-------------
|.71|96.|432|
|4.9|2.3|61.|
|326|.41|.59|


Is there a way to solve it without a forcing chain ?

[ronk]

Is there a way to solve it without a forcing chain ?

It appears to require the xy-wing technique, which is the shortest forced chain AFAIK. Simple coloring (single digit) is also req'd.

[Wolfgang]

We found it After the swordfish in 7 you can eliminate 5 from r4c1 with simple coloring (or turbot fish). Then there's an xwing and another swordfish - great.
Also puzzle001 can be solved with simple coloring/turbot fish.
My friend loves pack 2 now too