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Everything posted by plasmid

  1. Warning: This is a problem I have not yet found an optimal (or even very good) solution to. But it seems awfully non-trivial, and not in a genre that I've seen before, so I'm throwing it out there for the Den. ( @bonanova that means you should take a look.) You have a pet mouse. It's an awfully cute mouse. Kind of like those mice on Pinky and the Brain. And you'd like to make it even cuter by teaching it some tricks. The only problem is that your mouse is, well... let's just say it has the brain of a mouse so it's kind of hard to teach it any tricks. But it is very good at eating food. In fact, it will always manage to find the closest morsel of food and go eat it, then find the closest from its new position and go eat that, etc. until it eats everything in sight. So, you'd like to "teach" your mouse to do some tricks given that behavior. The first exercise is to place morsels of food at the corners of a square and place breadcrumbs so the mouse runs to diagonal corners as much as possible. In other words, suppose you have a square with points A, B, C, D in clockwise order with the mouse starting at point A and you'd like to make the mouse go to point C (diagonal from point A), then point B (one of the two remaining), then point D (diagonal from point B). There are already some breadcrumbs at points B, C, and D (since there need to be breadcrumbs there if you want the mouse to stop at those points) and your goal is to place breadcrumbs to make the mouse go from A to C to B to D while placing as few breadcrumbs as possible. That first exercise might be a challenge for your kid brother, but for a BrainDen level challenge (the one I haven't convinced myself I've found an optimal solution for yet): Instead of a square, suppose you have a regular pentagon with points A, B, C, D, and E in clockwise order and want to get the mouse to go from A to C to E to B to D?
  2. If anyone tries asking people this question in real life, a follow up after they've heard that answer: If a ship with tourists from Europe sinks on the way from Alaska to Australia while in contested Chinese waters, where would the deceased passengers be buried?
  3. Push your feet upon on my pedals While the rubber meets the road Then as urge for fun unsettles Lose my grip, so off we go My engine wrapped around a tree Your limbs are but a price to pay All for this pursuit of glee On single foot now make your way
  4. Well, I've shown a lot of ways where Arcsin could win, but I don't actually prove that Arctan can win in cases that aren't covered in the above ramblings. An ideal solution would be along the lines of: "If the composition of the Praesidium meets these criteria then Arcsin has a strategy that's guaranteed to win, and if it doesn't fit those criteria then Arctan has a strategy that's guaranteed to win."
  5. Have been thinking about this for a little bit, and now ready to take a stab
  6. Right on! I wrote this riddle just after seeing essentially this
  7. I had to think about it a bit to convince myself that the statement at the end of the first paragraph is really true, but I believe it is. For anyone not seeing it easily:
  8. You're getting quite close, plainglazed.
  9. Getting warm, but still looking for something that's hidden while out in the open.
  10. I'm not a picture frame. Tough in my mind to interpret it as having been found only by those now dead. Also not a skydiver. I'm something more commonly known for grabbing everything. Not an excavator. I don't envision him hanging and then being hung by the same "man". And also not a shovel for similar reasoning.
  11. I watched the video, and overall liked it. Since you asked for feedback: with the video format, I think I would prefer to see the question and be told to pause to have time to think of the answer before it appears instead of having a set amount of time for each question, since with at least some of them you either know it or you don't right off the bat. As it is, I got a little annoyed waiting a minute for the answer if I already knew it. The other main comment is something DejMar sort of alluded to, that there are potentially multiple answers that would make sense for some of the riddles. In particular the second one, I also interpreted it as most likely being a gotcha where each number in the sequence is (n)/(n+1), so the final term x/1000 comes after 9/10 and should equal 10/11, meaning x = 10 x 1000 / 11. Only after realizing that it wouldn't be an integer did I decide that it probably wasn't what you intended to ask, so the answer should be the other thing I had in mind and be x = 999. With the light switch, when I saw it here I thought there must be three positions with something like "off" going to "medium", "medium" going either to "off" or to "high", and "high" going only to "medium" so there would be a unique answer -- after any even number of flips the switch must be back at "medium" -- whereas with the youtube version if you change directions during flipping you could either end up at the original position or 180 degrees away. For the question of painting 8s, I could have interpreted a couple of ways: you could argue that he would only paint 8 once (if it's referring to house number 8, or just the number 8 and not other numbers that happen to have 8 as a digit), that he would paint it 20 times (if you mean the total number of digits that are 8), or maybe even 19 times (if you mean the total number of houses with any 8 on them, although that's a less likely interpretation). DejMar commented on the ambiguity of whether the question with Little Johnny is talking about making it home with the original $300 dollars or the money that the man is offering, but I suppose that ambiguity needs to be present or else it wouldn't be much of a riddle. And the last question seems like it might be a bit offensive if asked to a woman. It might not be possible to make the questions entirely unambiguous, especially the question about Little Johnny since the ambiguity is what makes it a riddle in the first place, but sometimes simple things like saying "how many times does he have to paint the digit 8" can help make it unambiguous. In general, I would say to check for (and ask other people to check for) unintended ways that the questions might be interpreted.
  12. Not an escalator. If I remember correctly the track record here has been that people's guesses about the difficulty of their own riddles ended up having little to no correlation with how tough they were for everyone else, so who knows.
  13. A nice interpretation for that third and fourth line, but I'm not a cross.
  14. I’d grab ahold of all I can Relentless in my spree Amidst the crimes I hung a man And then the man hung me I met some more of my own kind We really got along In open hid where none could find Except the dead and gone A pretty easy one to follow up on that walloping
  15. Afraid there's still a square lurking there And I'll take one more shot before bed
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