## July 08, 2011

### Friday Puzzles #112

My fellow puzzle blogger Grant Fikes was kind enough to give me a preview of some upcoming puzzles he plans to feature on his blog, and you should definitely watch out for his entry next Monday. He also provides inspiration for this week’s puzzle, which I’m sure all my dearest readers will be pleased to see is on time again.

The idea is simple – make a 10×10 fillomino, with certain symmetric constraints. This is my first effort, which presumably is null and void for the purposes of the contest, but will hopefully act as inspiration for anyone else who might want to have a go. Upon re-solving this, it’s slightly less easy than I thought it was, which makes me think it’s a bit of shame I can’t enter this, but then I suppose I shall have to come up with something better than this. Anyhow, bearing in mind I haven’t made many fillomino (4? 5?), I’m going to be a bit cagey and call this a medium. Enjoy!

EDIT: What I initially had in mind was probably medium, but as Jack points out below what I initially had in mind had two solutions. Anyhow, this unique version gets cranked up to hard!

#140 Fillomino – rated hard

[blockquote mark-up still apparently not working]

All puzzles © Tom Collyer 2009-11

### 6 comments by 2 or more people

1. #### Jack

I’m getting some ambiguity between the 2 and the 6 in the lower-right. Might want to check that. But otherwise a nice puzzle.

Looking forward to your test on LMI this weekend.

08 Jul 2011, 01:37

2. Ah you’re right. That 2 was initially supposed to be a 5, but then it turned out I was forced to use up too many 5’s as givens. I think I can fix this one to get it solving uniquely by swapping the position of one of those 2’s and 6’s bottom right, but it kinda makes the solve harder and more fiddly…let me double check…

08 Jul 2011, 01:44

3. #### y

I think this version is also only medium. The new possibility the 2-6 swap allows that has to be eliminated by fiddling can be removed also by counting.

08 Jul 2011, 05:35

4. #### Rupert Swarbrick

As y said, counting makes this doable at the bottom right. I was really surprised to manage it, given this is the first fillomino I’ve done! Incidentally, I think your link to Nikoli is broken for this puzzle: I get a 404, but this page does work.

Anyway, I enjoyed this: I was really surprised by how the shapes turned out, which is always nice!

08 Jul 2011, 08:46

5. Hmm ok…well perhaps that’s just my naivety as a fillomino creator. I’ve always thought that when I’ve solved these before suddenly having to count remaining squares is a little inelegant and not the first thing that comes to mind, especially when having to do this is completely unprompted by how the puzzle has been solving previously to that point.

In my mind the (slightly) broken easier version of this puzzle solved a lot more elegantly, but there we go. Perhaps the discrepancy in the difficulty ratings is because that was really an easy. As I say, I don’t have much idea how to rate fillomino puzzles. I have no idea at all what I’d rate the filllomino on the LMI test as, for example.

08 Jul 2011, 12:31

6. #### mathgrant

Not bad for what seems to be your first attempt at a Fillomino (excluding the previous version, which I missed, but gather had multiple solutions), especially given the restraint you wrangled with! As you expected, I don’t think I’d be able to accept this as a contest entry, since I’d prefer to have the readers judge the puzzles without being explicitly told who authored what, and publishing the puzzle on your blog defeats that purpose, obviously. laughs But that doesn’t disqualify you from crafting another puzzle in the meanwhile and sending that one in! :)

Also, I agree that counting makes the ending manageable.

10 Jul 2011, 03:38

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## Information

Welcome to the blog of current UKPA sudoku champion, two-time Times national sudoku champion and general logic puzzle fan Tom Collyer.

Home of the original Friday Puzzles, each Friday I publish a 100% original and handmade logic puzzle, inspired by the world-famous Nikoli company.

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