Shortest-possible walking tour to 81,998 bars in South Korea • Hacker News Board

Re: Shortest-possible walking tour to 81,998 bars in South Korea

#141

Post by inasio » Thu, Apr 24, 2025, 4:57 PM UTC

alexchamberlain wrote: post #50

inasio wrote: post #32

Earlier quoted context omitted.

Proof in this case is that the upper bound and the lower bound of the solver converged. This is not like a SAT solver where the solution itself can be trivially evaluated to verify the solution, it requires trusting that the solver does what it's supposed to be doing, similar to what happens when you solve a MILP with Gurobi or CPLEX.

Is the solver guaranteed not to land in a local minima/maxima?

The solver generates a relaxed lower bound that indicates how far they could be from the global optimal solution. The moment that the lower bound improves enough to match a path they can guarantee that it's the global optimum

Re: Shortest-possible walking tour to 81,998 bars in South Korea

#142

Post by pugworthy » Thu, Apr 24, 2025, 5:42 PM UTC

During COVID I made it a goal to walk every street in my town using the web-based CityStrides (https://citystrides.com/) tracker. It keeps tracks of streets you have walked and lets you know what percentage of a town you have walked. It didn't optimize my routes for coverage, but it was a fun mental puzzle to plan out my walks to hit as many streets as possible without duplication. An automated tool might be fun, but doing it by hand was part of the journey as it were.

As you browse the CityStrides site you can find people's LifeMaps which show all their walking. Some people have done amazing amounts of walking. See this user for example and their coverage of Paris, France...

https://citystrides.com/users/15259/map#48.85741101618777,2....

Re: Shortest-possible walking tour to 81,998 bars in South Korea

#143

Post by ZeroTalent » Thu, Apr 24, 2025, 7:52 PM UTC

deepspace wrote: post #138

mherkender wrote: post #120

Earlier quoted context omitted.

South Korea has 5x the population of Ohio, but around 27x the number of bars [1]. So it really is a lot of bars. [1] https://www.ibisworld.com/us/industry/ohio/bars-nightclubs/1...

As someone married to a Korean, I am not surprised in the least. Every single one I have met (males at least) drinks like a fish. It is impossible to describe to a westerner just how ingrained the drinking culture is over there.

They drink more than Eastern and Northern Europeans. It's insane!

Re: Shortest-possible walking tour to 81,998 bars in South Korea

#144

Post by numpad0 » Thu, Apr 24, 2025, 9:47 PM UTC

bbno4 wrote: post #44

notesinthefield wrote: post #8

I am overwhelmed with the thought of nearly 82 thousand bars within a country roughly the size of Ohio.

americans always compare massive cities to empty states

The entire US and North America is massively more empty relative to almost anywhere else, even most perceptually sparse countries. Many of European countries are 5-10x denser than US.

  0: https://en.wikipedia.org/wiki/List_of_countries_and_dependencies_by_population_density

Re: Shortest-possible walking tour to 81,998 bars in South Korea

#145

Post by robocat » Thu, Apr 24, 2025, 10:06 PM UTC

apocalyptic0n3 wrote: post #126

skrebbel wrote: post #118

Earlier quoted context omitted.

The parking minimum is for taxis?

It's pretty common for people drive to the bar, get drunk, taxi/Uber/Lyft/DD home, and then return the following day to get their vehicle. I don't think it makes sense personally, but I also don't drink at all so I'm not a great judge here.

Makes perfect sense if people are not planning on having a big night and then do.

You can see people taxi/uber into a place if they are definitely planning to get blathered.

Re: Shortest-possible walking tour to 81,998 bars in South Korea

#146

Post by marcellus23 » Fri, Apr 25, 2025, 3:57 PM UTC

nurettin wrote: post #136

marcellus23 wrote: post #123

Earlier quoted context omitted.

That's not true. The tour is 16.2 billion light years long, so even at the speed of light, it would take more than the current age of the universe to travel. Stars will move a lot over that period of time.

Yes I was assuming instant travel, even with one star the trajectory will be nonlinear.

That doesn't make sense to me. If you're assuming instant travel, then of course you don't need to account for stellar drift. Your response talking about stars "moving on roughly the same trajectory" doesn't make sense in that context. And anyway the GP was obviously not talking about instantaneous travel.

Re: Shortest-possible walking tour to 81,998 bars in South Korea

#147

Post by bscphil » Mon, Apr 28, 2025, 3:47 PM UTC

gku wrote: post #64

If you find this impressive, take a look at the 1.33 billion stars TSP solution provided by the same authors. - Gaia DR2 (1,331,906,450 Stars): https://www.math.uwaterloo.ca/tsp/star/gaia2.html > "The tour is at most 1.0038 times the length of a shortest-possible route."

Unfortunate - they didn't pin the version of Three.js they were using for the interactive viewer at https://www.math.uwaterloo.ca/tsp/star/star10m_tour.html

And as a result it's been broken since May 2022: https://github.com/mrdoob/three.js/releases/tag/r141

I downloaded the HTML file and replaced the link with a versioned one, and the viewer still works just fine.