you have to get heat water and eletric to each house but no lines can cross
heat water eletric
house 1 house2 house3
you can use a infinte amount of paper
Heehee, I do decision maths so I can prove that that's impossible. =P
Why did the vector cross the road?
It wanted to be normal.
I think that is a cheap way out. Represent each house as a vertex. Now try it.
Then Eulers formula comes into play.