I am a newbie to graph theory and this may possibly be quite a strange quesion.
Can a graph exist such that contains both weighted and unweighted edges? If yes, could you also let me know what can be a practical application of such a graph?
I am now writing a tiny program that tries to do a requested job, e.g. to find the shortest path with a given graph, source, and destination. I am wondering what to do if the given graph contains both weighted and unweighted edges. If it is an impossible case at all, then I can feel free to simply throw an exception. But, if it is a possible case, then I would like to study it further more.