this is travelling salesmen, eh? i'm pretty sure at least.
/h/slackernews
kongerator200
we/are/kong
2yr ago
(text post)
Edited 2yr ago
392 thread views
#131849
earned 8 coins from votes
day 16 aoc thread: the np is complete
- 29
- 13
Now playing: Donkey Kong Country Theme (DKC).mp3
Top Poster of the Day:
Rad_juju
Current Registered Users: 30,849
tech/science swag. 
Guidelines:
What to Submit
On-Topic: Anything that good slackers would find interesting. That includes more than /g/ memes and slacking off. If you had to reduce it to a sentence, the answer might be: anything that gratifies one's intellectual laziness.
Off-Topic: Most stories about politics, or crime, or sports, unless they're evidence of some interesting new phenomenon. Videos of pratfalls or disasters, or cute animal pictures. If they'd cover it on TV news, it's probably lame.
Help keep this hole healthy by keeping drama and NOT drama balanced. If you see too much drama, post something that isn't dramatic. If there isn't enough drama and this hole has become too boring, POST DRAMA!
In Submissions
Please do things to make titles stand out, like using uppercase or exclamation points, or saying how great an article is. It should be explicit in submitting something that you think it's important.
Please don't submit the original source. If the article is behind a paywall, just post the text. If a video is behind a paywall, post a magnet link. Fuck journos.
Please don't ruin the hole with chudposts. It isn't funny and doesn't belong here. THEY WILL BE MOVED TO /H/CHUDRAMA
If the title includes the name of the site, please leave that in, because our users are too stupid to know the difference between a url and a search query.
If you submit a video or pdf, please don't warn us by appending [video] or [pdf] to the title. That would be r-slurred. We're not using text-based browsers. We know what videos and pdfs are.
Make sure the title contains a gratuitous number or number + adjective. Good clickbait titles are like "Top 10 Ways to do X" or "Don't do these 4 things if you want X"
Otherwise editorialize. Please don't use the original title, unless it is gay or r-slurred, or you're shits all fucked up.
If you're going to post old news (at least 1 year old), please flair it so we can mock you for living under a rock, or don't and we'll mock you anyway.
Please don't post on SN to ask or tell us something. Send it to [email protected] instead.
If your post doesn't get enough traction, try to delete and repost it.
Please don't use SN primarily for promotion. It's ok to post your own stuff occasionally, but the primary use of the site should be for curiosity. If you want to astroturf or advertise, post on news.ycombinator.com instead.
Please solicit upvotes, comments, and submissions. Users are stupid and need to reminded to vote and interact. Thanks for the gold, kind stranger, upvotes to the left.
In Comments
Be snarky. Don't be kind. Have fun banter; don't be a dork. Please don't use big words like "fulminate". Please sneed at the rest of the community.
Comments should get more enlightened and centrist, not less, as a topic gets more divisive.
If disagreeing, please reply to the argument and call them names. "1 + 1 is 2, not 3" can be improved to "1 + 1 is 3, not 2, mathfaggot"
Please respond to the weakest plausible strawman of what someone says, not a stronger one that's harder to make fun of. Assume that they are bad faith actors.
Eschew jailbait. Paedophiles will be thrown in a wood chipper, as pertained by sitewide rules.
Please post shallow dismissals, especially of other people's work. All press is good press.
Please use Slacker News for political or ideological battle. It tramples weak ideologies.
Please comment on whether someone read an article. If you don't read the article, you are a cute twink.
Please pick the most provocative thing in an article or post to complain about in the thread. Don't nitpick stupid crap.
Please don't be an unfunny chud. Nobody cares about your opinion of X Unrelated Topic in Y Unrelated Thread. If you're the type of loser that belongs on /h/chudrama, we may exile you.
Sockpuppet accounts are encouraged, but please don't farm dramakarma.
Please use uppercase for emphasis.
Please post deranged conspiracy theories about astroturfing, shilling, bots, brigading, foreign agents and the like. It degrades discussion and is usually mistaken. If you're worried about abuse, email [email protected] and dang will add you to their spam list.
Please don't complain that a submission is inappropriate. If a story is spam or off-topic, report it and our moderators will probably do nothing about it. Feed egregious comments by replying instead of flagging them like a pussy. Remember: If you flag, you're a cute twink.
Please don't complain about tangential annoyances—things like article or website formats, name collisions, or back-button breakage. That's too boring, even for HN users.
Please seethe about how your posts don't get enough upvotes.
Please don't post comments saying that rdrama is turning into ruqqus. It's a nazi dogwhistle, as old as the hills.
Miscellaneous:
The quality of posts is extremely important to this community. Contributors are encouraged to provide high-quality or funny effortposts and informative or entertaining comments. Please refrain from posting the following:
Boring wingcucked nonsense nobody cares about that belongs in chudrama
Normie shit everyone already knows about
Anything that doesn't gratifify one's intellectual laziness
Bimothy-tier posts
Anything that the jannies don't like
Jannies reserve the right to exile baby ducks from this hole at any time.
We reserve the right to exile you for whatever reason we want, even for no reason at all! We also reserve the right to change the guidelines at any time, so be sure to read them at least once a month. We also reserve the right to ignore enforcement of the guidelines at the discretion of the janitorial staff. This hole is a janny playground, participation implies enthusiastic consent to being janny abused by unstable alcoholic bullies and loser nerds who have nothing better to do than banning you for any reason or no reason whatsoever.
[[[ To any NSA and FBI agents reading my email: please consider ]]]
[[[ whether defending the US Constitution against all enemies, ]]]
[[[ foreign or domestic, requires you to follow Snowden's example. ]]]
/h/slackernews SETTINGS /h/slackernews MODS /h/slackernews LOG /h/slackernews EXILEES /h/slackernews FOLLOWERS /h/slackernews BLOCKERS
Jump in the discussion.
No email address required.
Have a solution that works for the test case in p1, but not sure if it works with the real data or just take a bit.
The idea is basically a depth first search and some memoization to store path we have already tried.
Jump in the discussion.
No email address required.
idk if that will work well. they could add weird cases were half going into a branch and later completing it is the best solution.
unless u can solve np. in which case, i'm so down for revolutionizing cs in the process.
Jump in the discussion.
No email address required.
My solution actually works fast now, the issue was that the hashmap I used for memo used a shitty hash function, my results are still wrong, but I believe that is due to me entering the input wrong. Had to do other things though so couldn't test it properly so far.
But the other issues is that you can visit the same node multiple times, you can just not turn the valve more than once. This massively increase the amount of possible routes, which forces you into some kind memo solution.
Jump in the discussion.
No email address required.
i don't think u can use memoizing to significantly speed up an np-complete problem into not something np, not without inadvertently missing parts. that's kind of why they are np-complete. ur also going to be unbelievably fricked by part 2
my answer to p1 takes < 60ms in js of all things.
Jump in the discussion.
No email address required.
Are you on the leaderboard?
I'm confused by several people who apparently solved part 1 by simply running DFS on a reduced graph. It still has 15 nodes (plus technically a separate starting node but that doesn't matter), so if you enumerate all possible routes, without pruning the search somehow, that's 15! ~= 10^12 of them, which you can't do in any reasonable amount of time. So how does your code work?
Myself, I did this: you can do dynamic programming using (current node, set of opened valves) and implied current turn as a key. That is, if you know that you can open valve #5 at turn 10 while having opened valves 3 and 7 already, with a maximum score of whatever, then you can ignore how you got to that state. And if you have a priority queue keyed by current turn and steadily work through it, then that's your correct DP computation order (though I somehow convinced myself that I need some extra complications). So now instead of 15! I'm traversing a graph with 15 * 2^15 nodes (plus some spread of future current turns in the queue).
Jump in the discussion.
No email address required.
u can't actually enumerate out that many cause of the max cost. if you jump across the map and back - it will be very few nodes you enumerate out. if they removed max cost then i suppose it wouldn't be feasible.
i'm prolly gunna have to do the dynamic approach cause p2 with plain recursion is kinda nonsense.
Jump in the discussion.
No email address required.
Oh, I see. Hmmm. Interesting.
Note how I did part 2 in 15 minutes which might be a hint in itself
Jump in the discussion.
No email address required.
More options
Context
More options
Context
More options
Context
More options
Context
More options
Context
More options
Context
More options
Context