Djikstra

public CursorList<RouteInfo> minCostRoute(String startName, String endName){
		// TODO: Find the route from start to end that has minimum cost
                LinkedNodeBasedList<RouteInfo> minRoute = new LinkedNodeBasedList();
		Vertex<String> start = cities.get(startName);
		Vertex<String> end = cities.get(endName);
		// If there isn't a vertex, the city doesn't exist
                for(Vertex<String> v: deliveries.vertices())
                {
                    if(v.equals(start))
                    {
                        v.put("COST", 0.0);
                    }else{
                    v.put("COST", Double.MAX_VALUE);
                    }
                }
                HeapPQ<Vertex<String>, Double> minCost = new HeapPQ();
                for(Vertex<String> v: deliveries.vertices())
                {
                    PriorityQueueEntry I = minCost.enqueue(v, (Double)v.get("COST"));
                    v.put("LOCATOR", I);
                }
                while( minCost.isEmpty() == false)
                {
                    Vertex<String> v = minCost.dequeue().element();
                    for(Edge<RouteInfo> e: deliveries.incidentEdges(v))
                    {
                        Vertex<String> opp = deliveries.opposite(v, e);

                        double thruEdist = Double.parseDouble(v.get("COST").toString()) + e.element().getCost();
                        if(thruEdist < (Double)opp.get("COST"))
                        {
                            opp.put("COST", thruEdist);
                            minCost.changePriority((PriorityQueueEntry)opp.get("LOCATOR"), thruEdist);
                            opp.put("EDGE", e);
                        }
                    }

                }
                Vertex<String> v = end;
                Edge<RouteInfo> eri = (Edge<RouteInfo>)v.get("EDGE");
               minRoute.add(eri.element());
                v = deliveries.opposite(v, eri);
                while(v != start)
                {
                    eri = (Edge<RouteInfo>)v.get("EDGE");
                    minRoute.addBefore(minRoute.first(), eri.element());
                    v = deliveries.opposite(v, eri);
                }

		if(start==null || end== null) {
			return null;
		}

		return minRoute;
	}