On Jul 27, 2006, at 9:20 PM, Alejandro Aragón wrote:

Hello, I'm working with undirected graphs and I was wondering if there is an algorithm that traverses all the edges in the graph in such a way that this task is optimized. That is, if you draw a graph with a pencil, the number of times that you should lift the tip of the pencil is minimized. Can anyone give me a hint on this?

I don't know any algorithms off-hand that solve your particular problem, but it sounds like a variant of an Euler tour (or Euler path). You might want to start there. Doug