title: Find a path with alternating colors in a 2-color graph
body: <p>I'm given a graph G=(V,E) , with a color function C: E-->{red,blue} (e.g an edge can be colored in one of those 2 colors)</p>
  
  <p>I would like to find a path, not necessarily simple (meaning the path is allowed to include an edge or node more than once), which is alternating in colors - that means that every edge's color in the path is different than the previous color in the path.</p>
  
  <p>There aren't any more constraints, but I was told that this could be achieved in linear time.</p>