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Topology puzzle question?
Imagine 3 points represent gas, water and electricity suppliers. 3 more points represent houses. Is it possible to link every house to every utility without crossing wires/pipes?
I think not unless it is located on a torus shaped planet.
2 Answers
- 1 decade agoFavorite Answer
This is a question about planar graphs:
http://en.wikipedia.org/wiki/Planar_graph
This graph is the non-planar K_(3,3).
There's some interesting stuff in that wiki article.
Source(s): http://en.wikipedia.org/wiki/Planar_graph
