title: Add new edge to graph and find new spanning tree in O(n)
body: <p>Suppose we are given the minimum spanning tree T of a given graph G (with n
  vertices and m edges) and a new edge e = (u, v) of weight w that we will add to G.
  Give an efficient algorithm to find the minimum spanning tree of the graph G + e.
  Your algorithm should run in O(n) time to receive full credit.</p>
  
  <p>(c) from Skiena manual</p>
  
  <p>Start Prim or Kruskal alg from u or v until we reach a fragment of the given spanning tree path?  Seems the new spanning tree won't change a lot from one new edge.</p>