Whoops I should’ve been clearer I meant two neighbours within the donut. So the inside ones could be 2 or 3 colours and then the donut is one of the other 2 or the 1 remaining colour.
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Blyfh@lemmy.world 11 months agoBut each small country has three neighbors! Two small ones, and always the big donut country. I attached a picture to my previous comment to make it more clear.
Afrazzle@sh.itjust.works 11 months ago
Blyfh@lemmy.world 11 months ago
You’re right. Bad example from my side. But imagine the four small countries being four parts of another donut that encompass a smaller country. Then it would be impossible.
Afrazzle@sh.itjust.works 11 months ago
That map is actually still quite similar to the earlier example where all 4 donut hole countries are the same. Once again on the right is the adjacency graph for the countries where I’ve also used a dashed line to show the only difference in adjacency. Image
neumast@lemmy.world 11 months ago
Make purple yellow and one of the reds purple.
SuddenDownpour@lemmy.world 11 months ago
…There is no purple though?
Pronell@lemmy.world 11 months ago
In your example the blue country could be yellow and that leaves the other yellow to be blue. Now no identical colors touch.
wazoobonkerbrain@lemmy.world 11 months ago
You still have two red countries touching each other, what are you talking about?
Pronell@lemmy.world 11 months ago
Oops I meant the red one goes blue.