This is the fifth in a series of videos about the graph data structure. It explains how Dijkstra’s shortest path algorithm can be implemented for a weighted graph in VB.NET. This particular implementation involves coding up a Dijkstra class, whose constructor is passed a graph’s adjacency matrix as a parameter from which it can generate the shortest path information. The shortest path information includes two arrays, one containing the shortest distances of each vertex from a starting vertex, and another contain a list of previous vertices from which the shortest sequences of vertices can be implied. Selection of the next unvisited vertex closest to the start, the so called ‘greedy’ part of the program, is performed by a separate function. The shortest path information is returned by this class via read only properties and is displayed in a ListBox on a form.