*Kia*
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http://home.cwru.edu/~jnt5/Planarity/
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Mental Challenge SFW - Planarity @CWRU
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mattmns
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When does this thing end?
Townsend
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*Kia* said:
It gets complicated quick...
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mattmns
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Yep, just beat level 5, but I got to stop there, for now 
Cool game, though.
Cool game, though.
*Kia*
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I wimped out on level 3 but I am really tired so maybe tomorrow eh?
jma2001
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Interesting, would anyone like to take a shot at explaining the mathematical concepts behind this game? It reminds me of the Bridges of Konigsberg problem. From my limited experience with the game, it seems that the secret is to place the nodes having the most edges in the center, while the nodes having only two or three edges can be arranged around the perimeter.
mattmns
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jma, that is what I was doing.
Science Advisor
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The Bridges of Konigsberg is a graph theory problem, and this game certainly has to do with graphs (a graph is just a thing with "nodes" as you call them, and edges connecting nodes in some manner). If I recall correctly, a planar graph is any graph that can be drawn in the plane such that no two edges cross each other. If you have 4 nodes forming a square, and edges connecting every pair of points, then you'll get a square with an X in the middle. But you can take one of the diagonals and have that edge go from one corner outside and around the square to the opposite corner, so it's a planar graph.
So in this game, you show that each of the graphs are planar. I think in the Bridges problem, you are trying to find a special kind of circuit (Euler Circuit?). Whether a graph is planar and whether it contains a Euler Circuit may or may not be directly related (i.e. I don't know if there's a theorem that says whether a planar graph has a circuit, or something like that) but both are indirectly related as they both have to do with graph theory. Most of the above is based on sketchy knowledge from over a year ago, so I would recommend looking up some of these things:
Graph and Graph theory
Euler Circuit
Planar Graph
Bridges of Konigsberg
on a site like Mathworld.com.
So in this game, you show that each of the graphs are planar. I think in the Bridges problem, you are trying to find a special kind of circuit (Euler Circuit?). Whether a graph is planar and whether it contains a Euler Circuit may or may not be directly related (i.e. I don't know if there's a theorem that says whether a planar graph has a circuit, or something like that) but both are indirectly related as they both have to do with graph theory. Most of the above is based on sketchy knowledge from over a year ago, so I would recommend looking up some of these things:
Graph and Graph theory
Euler Circuit
Planar Graph
Bridges of Konigsberg
on a site like Mathworld.com.
jma2001
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Thanks AKG, that is just the sort of info I was looking for.
In case anyone is curious, here's what level 8 looks like. I'm out.
http://www.jma2001.com/lev8.jpg
In case anyone is curious, here's what level 8 looks like. I'm out.
http://www.jma2001.com/lev8.jpg
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*Kia*
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nice work.
I believe a Euler circuit is where each "node"/vertices is crossed only once.
I could well be wrong but unless that "mass" of lines has only 2 vertices with an odd number of arcs then there are not Euler on the other hand if they do only have the two then they could very well be Euler.
http://www1.coe.neu.edu/~lrussell/planatary.jpg
NO I did not get that far, some other clever person.
I believe a Euler circuit is where each "node"/vertices is crossed only once.
I could well be wrong but unless that "mass" of lines has only 2 vertices with an odd number of arcs then there are not Euler on the other hand if they do only have the two then they could very well be Euler.
http://www1.coe.neu.edu/~lrussell/planatary.jpg
NO I did not get that far, some other clever person.
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mattmns
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Pff, I was about to post a screenshot of level 8 completed, not anymore 
Nice work Kia!
Nice work Kia!
neurocomp2003
- 1,359
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i finished level 5 in 5min...now I'm sick to my stomach can you save the game?!? i missed all the gui buttons because i quit X. My only tactic is to take all the degrees of 2 and move them as close the edge that they adjacent to...wsih you could move groups...
neurocomp2003
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ok i decided to play again level 6 took me not to long maybe 5-7 min but level 7 I'm well past 15 minARG .,..ok is that timer accurate because it says it only took me12min. 9 min on level 9
NOOOOO...i finished level 10 and it tells me that a flashscript is running really slow and to abot...then it stalled the game!.
NOOOOO...i finished level 10 and it tells me that a flashscript is running really slow and to abot...then it stalled the game!.
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jma2001
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That happened to me, too. Click 'No' (as in, no, don't abort the script) and wait. You might have to click 'No' a few times, but it will finish eventually.neurocomp2003 said:
jma2001
Gold Member
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It's true, I have no life ... 
http://www.jma2001.com/lev13.jpg
http://www.jma2001.com/lev13.jpg
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Townsend
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Hell no, that is crazy...
are you using trial and error to figure out what works or did you work out an easier way?
are you using trial and error to figure out what works or did you work out an easier way?
jma2001
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When I was a kid, I spent a lot of time drawing mazes on big sheets of paper, so I guess I developed an ingrained sense of how pathways fit together.Townsend said:
There is a method, it's hard to explain exactly, but in general:
When you click on each node, you will notice that the other nodes it is connected to are highlighted in red. I begin by going around the circle, clicking on each node one by one, and moving it to a point that is roughly equidistant between the other highlighted nodes. That way, all the nodes that are connected to each other are grouped together in the same general area.
Then, I choose one small area on the perimeter and untangle it. Nodes with two or three edges always go to the outside, four-edge nodes go to the center. Move the untangled piece into a corner, as far away from the other nodes as possible.
From there, as cliched as it sounds, it is simply a matter of taking one node at a time, and moving it from the tangled area to the untangled area. There is only one place that each new node can go, so that it is not crossing any of the edges in the untangled grouping.
Every now and then, if you get stuck, go back to the trick of dragging each tangled node to a position that is roughly equidistant between the other connected nodes. That will get you back on the right track.
In the screenshot that I posted, the original untangled area was in the upper right corner. You can see that, as I worked from the upper right outward, the lines connecting the nodes got longer and longer, as I dragged them into place from the lower left to the untangled area.
JamesU
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I'm currently on six, and scared, you should see it!
*Kia*
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mattmns said:Pff, I was about to post a screenshot of level 8 completed, not anymore
hahaha not I, some other clever person
VVVVV - posted this under the screen shot - VVVVV
*Kia* said:
Nomy-the wanderer
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jma2001
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This has reminded me of a pencil and paper game that I learned from a high school math teacher. Take a blank sheet of paper, and draw on it twenty pairs of circles, numbering each pair from one to twenty. That is, draw two circles in random locations, and label them both '1'. Then draw two more random circles and label them '2', and so on, up to '20'. So you end up with forty numbered circles on the page.
Then, without lifting the pencil from the page, and without crossing any lines, connect each pair of circles with a continuous line. Obviously the first half dozen pairs are easy, but by the time you get to number twenty, the paper looks like a piece of modern art and it takes ten minutes of snaking the pencil around to find a path to the other circle. It also helps to have a sharp pencil for squeezing through narrow passages! A very simple game, but fun for anyone who is interested by abstract patterns.
Then, without lifting the pencil from the page, and without crossing any lines, connect each pair of circles with a continuous line. Obviously the first half dozen pairs are easy, but by the time you get to number twenty, the paper looks like a piece of modern art and it takes ten minutes of snaking the pencil around to find a path to the other circle. It also helps to have a sharp pencil for squeezing through narrow passages! A very simple game, but fun for anyone who is interested by abstract patterns.
Nomy-the wanderer
- 172
- 1
Level 14 took me 32 minutes, I'm gettin tired...Anyone knows how many levels is that?
Nomy-the wanderer
- 172
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After endless appearences of this error, i got sick and bored, I've finished level 15.. :zzz:
hypatia
- 1,191
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Well at least I know I am not a idiot savant..lol I am stuck at 5.
moose
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My smart friend just got to level 20...
http://1337moose.com/images/level20.JPG
heh, this is what his level 19 looked like when he finished
http://1337moose.com/images/level19done.JPG
http://1337moose.com/images/level20.JPG
heh, this is what his level 19 looked like when he finished
http://1337moose.com/images/level19done.JPG
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