Shortest Paths

  • Single Source, Multiple Targets:
    • Can represent shortest path from start to every vertex as a shortest paths tree with V-1 edges.
    • Can find the SPT using Dijkstra’s algorithm.
  • Single Source, Single Target:
    • Dijkstra’s is inefficient (searches useless parts of the Graph).
    • Can represent shortest path as path (with up to V-1 vertices, but probably far fewer).
    • A* is potentially much faster than Dijkstra’s.
      • Consistent heuristic guarantees correct solution.