A <spanning tree> is a connected acyclic subgraph containing every <vertex>. A <minimum spanning tree> minimizes the sum of edge weights over all spanning trees. In a three-vertex triangle with every edge weight 1, deleting any of the three edges gives a different spanning tree of total weight 2. Hence there are three minimum spanning trees; minimum total weight need not mean a unique tree.

Solution

Past exam of the year 1 of the computer science course of the University of Oxford / 2016 / Functional programming, design and analysis of algorithms (resit) / 8 / a / Solution

 Solution (source code)