LMI Puzzle Marathon

[detuned]

No-one started a thread yet, so I will!

Contest page: http://logicmastersindia.com/M201201P/
Discussion thread: http://logicmastersindia.com/forum/foru ... sp?tid=434

Slightly different idea this time round, each puzzle in the contest is to be solved in isolation, with best aggregate time looking to be the tie breaker. And you have all week to do this in!

Puzzles are biiiiiiiiiig! Well, the puzzle I contributed certainly is - see if you can tell which one it is!

[GarethMoore]

Puzzles are biiiiiiiiiig! Well, the puzzle I contributed certainly is - see if you can tell which one it is!

Well given the colour-coding of authors in the instruction book it was presumably Kakuro...

[debmohanty]

Thanks Tom for posting. I had been busy with setting up the submission site.

Alright, so Puzzle Marathon has started, and there are already some awesome performances. Hoping to see you all participate too.

[detuned]

I guess the instruction booklet is a bit of a giveaway. This has been a lot of fun so far, certainly some tough challenges for any solver...

[puzzlemad]

Five down five to go. Enjoying this greatly. Hopefully I'll be able to find time in the rest of the week. Thanks to all involved!

[drsteve]

Two down so far - will try to squeeze another in later...

[drsteve]

I would point out to those who are wary of the one hour per puzzle time implication - the two I've done so far weren't hour-long puzzles and a lot of people have beaten the hour mark on them...

[PuzzleScot]

I love the format of this, though I think the results will be fairly meaningless. Well done to all the authors!

I predict the contestants could be ranked by their longest single puzzle solve time, and end up with roughly the same order. I don't think it's spoiling anyone's fun to say the 4 puzzles I've done tonight have taken no less than 30, and no more than 90 minutes each. (admittedly I was watching a film concurrently with the longest solve, and compounded the extended time by having to erase half of what I'd done already on it! Lesson learned? nah... )

There's still a few I'm really not looking forward to, though I might change my mind after the after the event.

If you like these, you should seek out the 3 Marathon puzzles that TomC unnecessarily(*) appended to a contest back in July last year. They were fantastic! (*)They were worthy enough to have been done as a separate 'competition'.

[sknight]

I'm sort of hoping the results are not in the order of longest solving time, since once I went over an hour on the Samurai Sudoku, I decided that I might as well get a fresh start on it at a later time (all correct solutions past 1 hour are worth the same 100 points). That means my official solving time on that one is 15+ hours. When I popped open the contest page to put in my solution it was funny to see the minute counter over 900 minutes, and almost tempting to wait another hour to enter my solution just to watch it roll over to 4 digits.

That being said, the Samurai Sudoku is so far the only puzzle that's taken me much over one hour. The pentomino and black and white loop puzzles were both about an hour for me, the kakuro about 45 minutes, and most of them have been right around a half hour. I'm not a particularly fast solver, though, and your mileage may vary. I'm just not a good pentomino solver, though I rather liked the design of the puzzle Also, I haven't tried the Graffiti Snake one, though since it's billed as "medium" I'm hoping it's not going to be as long and nasty as the sudoku.

I do generally like the format of this one. I'm one of those "doesn't always have a fast time, but will solve it eventually" puzzlers, so having any sort of contest where I get a reward for taking the time to finish all the puzzles even if I'm sort of slow is fine with me. I'm more comfortable taking my time to check my solution and re-count the answer key and so on, so I haven't had any false solutions thus far, which is also refreshing.

Anyway, the contest is still up and running for several more days, so anyone with some blocks of free puzzling time should definitely try at least a few of the puzzles.

[emma]

I don't think you need worry about longest solving time - I've been making a real hash of one of them, and the clock is now ticking at a couple of days on that one.

[drsteve]

Damn - not convinced that I'm going to have time to attempt all of these by tomorrow... FIngers crossed, but life seems to be happening at the moment. Life is rather annoying, isn't it?

[PuzzlerNickG]

10 of 10 done for me now. I was rather slow, but the only one I really messed up was Different Neighbours, so that ended up being left overnight. Kakuro and Sudoku became leisurely solves since it quickly became clear I wasn't going to solve them within an hour.

All in all, a very enjoyable set of puzzles.

[emma]

Got there - was not keen to do the braille one, but did it relatively easily in the end.
Doing Different Neighbours in under an hour was an achievement considering I did the whole thing twice - I ended up printing two of everything for this one, as I seemed so error-prone.

[rodders]

Started this last weekend with good intentions of completing all puzzles, but have only managed to attempt 6 of them. That includes the Samurai Sudoku which I was leisurely working through whenever I could, but ended up leaving it 50% completed on a train on Thursday.... Haven't got the willpower to start it all over again!

Very enjoyable though, and even though time has got the better of me this time, I've enjoyed having a full week to work through the puzzles at my convenience.

[nickdeller]

Set about the task too late to complete it! Left myself Pentominoes, Kakuro and Braille to round up yesterday evening, had to bifurcate on the Pentominoes and established after two hours that neither fork worked... so didn't bother to attempt the other two! Nice puzzles though. Had great fun with the black and white loop repeatedly telling myself things like "No, Nick, a white circle DOESN'T mean you have to pass straight through it...", "No, you don't HAVE to turn in every circle..." and generally inviting myself to get a grip.

Generally - I like this competition format a lot, and would certainly make more time for myself to run a repeat to completion.

[PuzzleScot]

Yep, loved the puzzles (except Kakuro/Sudoku).Results are up
Astonishingly, motris' 27:05 on the sudoku was his worst solve time!!!

Excellent battle between James and Neil - separated by 6 points in the end! Neil, will you PLEASE go and buy a printer!!

[detuned]

If anyone wants any pointers with the kakuro, I'm happy to give them out now

[Nilz]

Neil, will you PLEASE go and buy a printer!!

But if I had a printer, I wouldn't have an excuse for losing to Tom S/ Palmer etc.

I don't think the lack of a printer affected me that much here actually. I used the work printer for some, and the rest- Tapa, Pentominoes, Graffiti, Small Regions and Wordsearch- weren't too awkward in Paint. The biggest annoynace was Kakuro- I clicked start before noticing that the work printer was broken. After 10 mins frantically searching for another one, I had to resort to Paint. I like to think I could've saved at least 20 mins on that one.

[kiwijam]

If anyone wants any pointers with the kakuro, I'm happy to give them out now

Definitely keen to hear your thoughts on that puzzle. To me it best fit the description of 'marathon' puzzle, I think I lost some time looking for more break-ins rather than grinding across the grid.

[detuned]

Haha, Deb just showed me a link where someone had gone off on one about kakuro in general, and how my puzzle magnified everything he hated about the puzzle. Anyhow - here are some thoughts:

- Generally there is only one break-in when I put together something as big as this. This tends to be towards the top-left (bear in mind I'm right handed!)
- I was a little concerned with the initial structure of the grid, as there are some regions which are disconnected from the main grid by either one or two cells. I decided to have a bit of fun with these - hence setting up a 9 next to a 9/8 and then having a 24 clue (9/8/7) next to a 21 clue (8/7/6) and so on.
- the general solving theme of the puzzle was having high-low style intersecting clues. By this I mean something like having a 2-clue 9 intersect with a two clue 16. This means that the 7 has to go in the common intersection.
- however I did develop this gimmick a bit further, so where on first glimpse there two possibilities for something, there'd be a 1 placed already in the corresponding clue. I could then set up cascades of these where you were entering 1,2,3 and so on.
- around the M (and the W) I also had a bit of fun with pairs stacked on top of each other. Here a bit of sudoku comes into play as I set up some forced pairs which then you let you solve the stack of pairs all at once. If I recall rightly you had something like a 14 clue being 5/9, with an 17 clue being 8/9, forcing a 15 clue to be 7/8 and a 13 clue 6/7, and maybe there was a 12 clue being 5/7 or something. Anyway the point was you'd notice one of the columns reduced to a 30 sub-sum, which tells you what to do with the initial 5.

But yeah, other than that, I don't think there was too much else to comment on with that. Deb was telling me with the samurai that the trick was that you could go round solving individual grids going clockwise from the top-left, but obviously if you were scanning over all the grid trying to look for a break-in then you are going to waste lots of time and cause yourself much frustration. I think you have something true in more generality here - if you find yourself stuck then further progress is likely to come from break-ins you have already made, but maybe you've missed something. I think there is a culture of trying to show off your puzzles on LMI (in fairness, why not!) so you can generally assume there is a "nice" solving path to a given puzzle rather than having to trawl across grids looking for multiple break-ins.

[MellowMelon]

- Generally there is only one break-in when I put together something as big as this...

This sounds really backwards to me. If either of this or this had only one break-in, do you think they would be any fun? I know the actual LMI Marathon puzzles are nowhere near that scale, but the same principle applies. I would think the time when you would want one break-in would not be when you're constructing something large.

My understanding of your reasoning is that the solver should not have to search the whole grid for more break-ins when they get stuck. The problem is that as solvers we don't know how many break-ins you put in or what the solving progression is. I'm always open to looking anywhere in the grid when I'm stuck because that's how you avoid missing something stupid somewhere else and losing a lot of time for it. So putting one break-in doesn't make things better; it arguably makes it worse because a solver trying to make sure they haven't missed something elsewhere when stuck will never find anything and just get even more frustrated. On the other hand, with multiple break-ins it can basically be like you have a number of smaller puzzles to work on simultaneously, which allows you to jump somewhere else if you're running into a wall at one part (sort of like on a normal LMI test).

I thought it was a nicely constructed puzzle in general and am not sure what about it magnifies the worst of Kakuro, but the very linear solve is something I would consider a mark against it.

[rob]

Haha, Deb just showed me a link where someone had gone off on one about kakuro in general, and how my puzzle magnified everything he hated about the puzzle. Anyhow - here are some thoughts:

- Generally there is only one break-in when I put together something as big as this. This tends to be towards the top-left (bear in mind I'm right handed!)

Ah, so I wasn't supposed to do the sums for all those disconnected areas… I solved again left to right now and it did go more smoothly than during the test. There, I was on course to finish just under 60 minutes before making an error during the trickiest part (the Ms).

Thanks for the puzzle, I enjoyed it!

Cheers
Rob