Problem proposals by Mathias
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Soon we will be in the run-up to Christmas, so naturally I have submitted a problem proposal about Easter egg colours. Rodion, you've got mail.
Mathias, Hi!
The problem E2C2S - try harder! is ready, thanks for it and for cooperation!
I'm a bit sorry for while modifying the code I got a glimpse to approach, but this anyway requires me to study a bit until I can try to solve it :)
Mathias, Thanks for this nice little problem. I found it very interesting. It is a pity that all of the answers are so close together but that clearly isn't an issue for people solving the problem. They only need to miss by one!
Hi Clive, you are absolutely right. I wrote earlier to Rodion: "You will notice that the results all look very similar - that is okay and it's even intended for people to think about why that is and how that could be exploited."
For future challenges, an LCG with larger parameters might well be used. :)
Mathias, thanks, looking into it!
UPD: problem is ready, thanks once more! As I added few lines of code for verifying the answer, I ask you please to review / test it if possible.
UPD2: and thanks to Vladimir for seemingly testing the problem and confirming it works at least sometimes :) Sorry for delays from my side, please.
Thanks Rodion. Good to see the checker code and how it works for problems where different answers are possible. The problem is clearly on the easy side ...
Mathias, good morning - and thanks for the puzzle :) Here it comes under #415. Needless to say I'm impressed with its brevity and toughness %)
P.S. it would be great if you can check the problem's page to see that none of my modifications to code and text break anything.
Thanks Rodion, looks all good. And in case anybody has issues or disagrees with the expected answers, please let me know.
Mathias, Thanks for a really good problem. I really enjoyed it.
Mathias, Hi! Thanks for this new one - it makes impression that I can try at least! :)))
BTW I do beseech to use additionally this mighty green button below on such an important occasions!
Mathias, This was an excellent new way of looking at an old problem. Two really good ones in quick succession!
Rodion, many thanks for the quick publication. And no need for the green button here, I'll keep that for truly urgent matters.
Clive, congratulations for being first solver to both recent problems. There is always some nervousness on my part until someone else proves the correctness of the expected solution, so it's good to get this ticked off.
'Smallest Message' was inspired by moxieman's recent 'Wormholes of Cygnus', and 'Unfortunate Bubble Sort' by ThereAreNoUsernamesLeftForMe (what a name!) and zelevin's discussion about an easier problem featuring this sorting algorithm.
new problems are an urgent matter :)
and no worry, it doesn't ring my phone at midnight - just sends private message to me via social network...
Initially I mistakenly thought the problem could be solved with bruteforce, obvious miscalculation (16! is not 2^16),
then I tried another naive approach of "weighing" groups of letters by their sum of positions and deciding on arrangment
from this - but even in the process of writing I suspected it won't work properly. Well, probably I have yet another
idea or two, but I definitely should try it with smaller example first, with pencil-and-paper! Still I'm amazed
how you come up with such problems (I don't quite see how is it "inspired" by the mentioned dialog) - given that
it both is expressed very simply, immediately yields a handful of vague ideas - and still seems to be pretty tough :)
Not giving too much away, but there are two small hints in the problem statement.
Number one is what moves are allowed/considered as swaps,
and you mention number two yourself: 16! is indeed not 2^16, but 2^16 is a much nicer number (and maybe the
reason why I picked 16).