this post was submitted on 09 May 2026
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[–] BarneyPiccolo@lemmy.cafe 9 points 7 hours ago

At $14.50 per hour, he's going to take the shortest route.

[–] Ethanol@pawb.social 8 points 8 hours ago (2 children)

This is actually quite fun and simple! Even if the problem and my following explanation look complicated :P

Let's look at the three dimensional case. One can parametrize a 3 dimensional cube as the Cartesian product of intervals [0, 1] x [0, 1] x [0, 1]. This means a cube is a set of points (a, b, c) where a, b and c are real numbers between 0 and 1. The 2 dimensional sides of the cube are then given by fixing one coordinate. That is, the 6 sides are

{0}    x [0, 1] x [0, 1], 
{1}    x [0, 1] x [0, 1], 
[0, 1] x {0}    x [0, 1], 
[0, 1] x {1}    x [0, 1], 
[0, 1] x [0, 1] x {0} and 
[0, 1] x [0, 1] x {1}. 

Now we just start in the middle of a side at (0, 0.5, 0.5). To get to the next side we walk towards an edge (0, 0, 0.5) and then to the middle of the next side (0.5, 0, 0.5). We iterate this process until we run out of sides with a fixed 0, then walk towards a side with a fixed 1 and continue there. That is:

   (0  , 0.5, 0.5)
-> (0  , 0  , 0.5) 
-> (0.5, 0  , 0.5) 
-> (0.5, 0  , 0  ) 
-> (0.5, 0.5, 0  ) 
-> (1  , 0.5, 0  ) 
-> (1  , 0.5, 0.5) 
-> (1  , 1  , 0.5) 
-> (0.5, 1  , 0.5) 
-> (0.5, 1  , 1  ) 
-> (0.5, 0.5, 1  ) 

This path basically spirals around the cube, going through every side only once. Here's a visualization (sorry, I'm no artist :P) visualization of this path on a 3 dimensional cube

The same procedure works on a 4 dimensional cube or any other higher dimension. For the 4 dimensional cube it goes like this:

   (0  , 0.5, 0.5, 0.5)
-> (0  , 0  , 0.5, 0.5) 
-> (0.5, 0  , 0.5, 0.5) 
-> (0.5, 0  , 0  , 0.5) 
-> ...
-> (0.5, 0.5, 0.5, 0  )
-> (1  , 0.5, 0.5, 0  )
-> (1  , 0.5, 0.5, 0.5)
-> (1  , 1  , 0.5, 0.5)
-> ...
-> (0.5, 0.5, 0.5, 1  )

This works for arbitrary dimension except for the 1 dimensional cube (which is just a line) because the "sides" there are the two end points of the line and not connected at all. Additionally note, that it is never specified how edges count in this problem, whether they somehow count towards a face or whether you're allowed to go back and fourth on edges. You could technically only walk along edges and step into the sides every now and then.

[–] BarneyPiccolo@lemmy.cafe 19 points 7 hours ago

You owe me $14.50 for reading that.

[–] Olhonestjim@lemmy.world 2 points 6 hours ago

I don't usually do this, but I'm gonna go out on a limb and say this didn't happen.

[–] Akasazh@lemmy.world 12 points 10 hours ago* (last edited 10 hours ago)

Too many people are obsessing about 4d topology in this thread. The real difficulty in the question is the non -deterministic pathfinding of the ant, in the absence of pheromones.

[–] kepix@lemmy.world 18 points 15 hours ago (2 children)

making sure you cannot solve it, so you are perfect for the job

[–] PuddleOfKittens@sh.itjust.works 20 points 12 hours ago (3 children)

Possible candidate responses:

  1. Solves it (too smart for job)
  2. "That's bullshit, who needs this for a $14.50/hr job?" (too intolerant of bullshit for job)
  3. Tries to solve it but fails (lacks self-awareness for job)
  4. Knows they can't solve it so doesn't even try (too lazy for job)
  5. Doesn't understand the question/comprehend what a hypercube is (too dumb for job)
[–] Ensign_Crab@lemmy.world 14 points 10 hours ago

Maybe they're trying to weed out all actual applicants because they're hiring the boss' kid.

[–] echodot@feddit.uk 10 points 11 hours ago (1 children)

You forgot option 6, spew a bunch of techno bubble at the HR person who will definitely not understand the problem themselves and wouldn't be able to tell if you'd answered it or not.

[–] Signtist@bookwyr.me 4 points 6 hours ago

That's just response 1 from the perspective of the HR person scoring it.

[–] plz1@sh.itjust.works 2 points 11 hours ago

I'd argue that 3 and 5 are actually selection qualities for a job paying that low, with a question like that. The rest are all dis-qualifiers of course.

[–] mirshafie@europe.pub 6 points 13 hours ago* (last edited 13 hours ago)

I believe this is sometimes the case. I was called for an interview with a group of 15 other people ones. We were like a class, being interviewed as a group, and were supposed to solve some problems together. Nobody in that group could solve even the simple, obvious problems - we're talking basic math and reading comprehension here. Got an email the next day informing me that they had I had not been selected for recruitment.

[–] MIDItheKID@lemmy.world 16 points 16 hours ago (1 children)

Sure. Draw the cube for me and I will plot it's path.

[–] cmhe@lemmy.world 10 points 14 hours ago* (last edited 14 hours ago) (2 children)
[–] Tja@programming.dev 24 points 14 hours ago (1 children)
[–] cmhe@lemmy.world 2 points 13 hours ago* (last edited 13 hours ago) (4 children)

No shit? Next thing you say that there are no 3d games, because there are no 3d monitors. And those that say they are 3d as well as VR are just faking it, by using two 2d projections instead of one.

[–] PuddleOfKittens@sh.itjust.works 5 points 12 hours ago

Just code up a lemmy plugin that lets you embed basic interaction for navigating 4D shapes, my dude. It's just basic eigenvectors.

[–] ThunderQueen@lemmy.world 6 points 13 hours ago

Just wait until they figure out how eyes work

[–] dream_weasel@sh.itjust.works 1 points 8 hours ago* (last edited 8 hours ago)

There are 2D monitors though.

You can project a 3d object into 2d space and you can do the same with 4d into 3d, but collapsing more than that generally loses too much information. Edit: If you include movement you can reduce this effect somewhat depending what you're doing.

Your portrait is now just a colored line the height of your subject, and this "4D cube" doesn't mean anything because it looks like a 3d cube with a smaller cube cut out of the middle of it. Unless you're really into geometry I guess it you dropped a /s.

[–] Tja@programming.dev 3 points 12 hours ago

You must be fun at parties

[–] AlolanYoda@mander.xyz 5 points 10 hours ago (1 children)

I still don't understand it. Can you rotate it along the W axis so I can visualize it better?

[–] dream_weasel@sh.itjust.works 2 points 8 hours ago

Sure thing boss.

[–] Meron35@lemmy.world 12 points 15 hours ago (2 children)

Entry level positions to Gregg's (fast food sausage roll chain) require 1000 word personal statements as part of online applications

[–] echodot@feddit.uk 5 points 11 hours ago

Yeah but you also get equity in the company so I think that's fair enough.

You have to be proven worthy before you are handed the recipe for the vegan sausage roll. I want to know what addictive substance they put in there.

[–] Tja@programming.dev 2 points 14 hours ago

Ever heard of ChatGPT?

[–] vithigar@lemmy.ca 13 points 16 hours ago (1 children)

Choose a starting face and remember it. Walk each face of a cell containing that face touching each face once much like you would a 3-cube.

Pick any adjoining cell and move into one of its faces from there, walk each of its faces saving the one opposite the face you started on for last.

From there you're on a shared face with the cell opposite your starting cell. Traverse this one in a similar manner to the last, but this time also visit the adjoining faces of each cell adjacent to the second cell you filled, before once again ending opposite the face you started on for this cell.

Now you're on a shared face with the final cell, opposite the face you started on. Walk around the remaining four faces and you're done.

[–] mirshafie@europe.pub 14 points 13 hours ago

Followed these steps, ended up on the ceiling of my neighbor's tea room.

[–] CromulantCrow@lemmy.zip 16 points 19 hours ago (2 children)

Okay, if you can explain to me in detail how four dimensional topology is going to be important to me while I'm stocking the shelves of your grocery store, I'll give you an answer.

[–] fibojoly@sh.itjust.works 3 points 9 hours ago

Listen, once you get the job, you'll discover the truth about those shelves. And all I'm saying is, it becomes relevant that you can find your way through four dimensional space. Okay?

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[–] bitteroldcoot@piefed.social 59 points 1 day ago (1 children)

This is a lot like when Boston PD was found to screen out all the smart applicants. Sometime the company wants an obedient idiot.

https://www.cbsnews.com/news/too-smart-to-be-a-cop/

[–] OwOarchist@pawb.social 27 points 1 day ago

Might actually be the case, lol.

Answer this question correctly (or even intelligently at all) and your application is rejected.

[–] pennomi@lemmy.world 81 points 1 day ago (7 children)

Every cube is four dimensional, assuming time as the fourth dimension. So it would travel forward in time at a relatively constant rate (since ants don’t typically walk at relativistic speeds [citation needed]) and it would traverse the other three dimensions in normal ant ways.

[–] adj16@lemmy.world 2 points 5 hours ago (1 children)

Unfortunately I don’t think this is true. Every 3D face is the intersection of a 2D plane with the upper and lower bounds of the 3rd dimension. So I think a hypercube “face” would be every 3D “plane” at both the very start time AND the very end time. Meaning the ant would need to immediately accelerate to light speed - so no time would pass - and then (otherwise) normally traverse the faces, wait until the end time, and then repeat the process in reverse (still at light speed).

[–] deft@lemmy.wtf 85 points 1 day ago

Damnnn bro. They gonna start you at $15 with that kinda mind.

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[–] Entertainmeonly@lemmy.blahaj.zone 27 points 23 hours ago* (last edited 22 hours ago) (3 children)

Four dimensional? That is a tesseract. This is impossible to describe how an ant would even interact with let alone touch all eight cells only once.

[–] olafurp@lemmy.world 1 points 9 hours ago

It's not hard to imagine a 2d square sliding across a 3d surface or a line traveling across a 2d plane so an ant travelling across a 4d surface is not that weird.

[–] Slashme@lemmy.world 3 points 12 hours ago

The ant is a mathematical metaphor - a point that can trace a path along any surface and can cross to another surface only by crossing an edge, but cannot leave the surface.

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[–] user1234@fedinsfw.app 10 points 20 hours ago (1 children)

Isn't a cube by definition a 3 dimensional object? If it were 4 dimensional, it would no longer be a cube.

[–] Mohamed@lemmy.ca 24 points 20 hours ago (1 children)

Its a generalisation. A 4d cube is a shape that has the same length in all 4 dimensions. You can also talk of 5d cubes, 6d cubes, etc. These are commonly called n-cubes: a 4-cube is a 4d cube.

There are also 4D spheres, even though spheres are definitionally 3D. They are called n-spheres.

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