The New Sudoku Players' Forum

[BakyX]

Hi. I try to solve this kakuro:



What should I do now ? I can't see way how to continue constructively.

Thanks.

[denis_berthier]

Hi BakyX,

Welcome on this forum

What should I do now ? I can't see way how to continue constructively.

If you keep track of the candidates and combinations, you should see the

naked-pairs-in-horiz-sector: r6{c4 c7}{n1 n2} ==> r6c6 <> 2, r6c6 <> 1, r6c5 <> 2

[Smythe Dakota]

Sometimes I find the "where can the N be in X" trick useful. The trick is to find the N and the X.

In this case, you can ask "where can the 2 be in the 23 in c5?" (Since 23 with 6 digits is either 1-2-3-4-5-8 or 1-2-3-4-6-7, there must be a 2 in there somewhere.) It is not difficult to rule out a 2 everywhere in that word except r2c5, so r2c5 must be a 2.

Bill Smythe

[BakyX]

denis_berthier: I can see that (r6c4,r6c7) is permutation of {1,2}, so r6c6 and r6c5 can't be 1 or 2. But what now ? Thanks.

Smythe Dakota: I understand it and it's nice. Thanks.

[denis_berthier]

denis_berthier: I can see that (r6c4,r6c7) is permutation of {1,2}, so r6c6 and r6c5 can't be 1 or 2. But what now ?

You can now have bivalue chains:

biv-chain[2]: hr6c0{n18 n27} - r6c1{n1 n2} ==> r6c2 <> 2
biv-chain[2]: hr3c0{n12349 n12358} - r3c4{n9 n8} ==> r3c5 <> 8, r3c3 <> 8, r3c2 <> 8

You should be able to find 3 more of the same kind

[BakyX]

Ah, where can I find definition of biv-chain and other your symbols ?

[denis_berthier]

Ah, where can I find definition of biv-chain and other your symbols ?

My general approach and its application to Kakuro (and several other logic puzzles) are described in my last book "Pattern-Based Constraint Satisfaction and Logic Puzzles", available:
- in print form here: http://www.lulu.com/shop/denis-berthier/pattern-based-constraint-satisfaction-and-logic-puzzles/paperback/product-20516172.html
- in free pdf form here: http://arxiv.org/abs/1304.1628