## Archive for the ‘Puzzles’ Category

### Logic Puzzle Hall of Shame

Wednesday, April 25th, 2007

My puzzle links page gets a decent number of hits. It’s sort of a best-of compilation of places to go to do (mostly logic) puzzles online. It’s for my own convenience, but I know other people are using it too. Check it out.

So, I might as well go off in the other direction. Today we welcome Puzzle Junction to the Hall of Shame for giving The Purdue Exponent a sample kakuro that’s impossible to solve. Ouch.

The Exponent is polling for a new puzzle to add along side the sudoku on the comics page. To that end they printed representative puzzles from several of the Puzzle Junction-supplied types. I was looking forward to it, being an avid puzzle fan.

So with great anticipation I turned to the sample kakuro and saw the puzzle pictured here. My first thought was “Wow, that’s got to be the hardest kakuro of that size I’ve ever seen!” To save some erasing, I headed over to Indigo Puzzles and typed it in to the kakuro assistant so I could do some experimentation. (I later typed it in at Jarek to get it typeset for this column.)

It was soundly rejected because it has multiple solutions. Sure enough, there are several sets of interchangeable digits that make it truly impossible to solve logically. There are at least six obvious solutions at first glance (that off-handed dis is dedicated to Pierre de Fermat).

For those who aren’t hopeless logic puzzle addicts, multiple solutions don’t make a puzzle easier. Many solution strategies depend on the fact that a proper puzzle has only one solution. This is especially true in kakuro. Besides, it’s against the rules.

So a big jeer to Puzzle Junction. Boooooooo! Their other puzzles are pretty lame too. I’m guessing their “Anagram Jumble” will win the poll, but it’s not as good as the brand-name kind. People do love the Jumble, though.

It’s not The Exponent’s fault, but it’s disappointing that kakuro doesn’t have a ghost of a chance. If they’d printed one that was of a reasonable difficulty, I think they might’ve got some nibbles. As-is, I doubt anyone who’d not see one before got very far before deciding it was a waste of time.