public PathResult dijkstra() {
PathResult p = new PathResult();
Map dMap = map.newInstance();
HashSet<Node> evaluated = new HashSet<Node>();
HashSet<Node> unevaluated = new HashSet<Node>();
HashMap<String, Double> dist = new HashMap<String, Double>();
HashMap<String, String> previous = new HashMap<String, String>();
for (int i = 0; i < dMap.getSize(); i++) {
Node toAdd = dMap.getNode(i);
unevaluated.add(toAdd);
dist.put(toAdd.getName(), Double.MAX_VALUE);
previous.put(toAdd.getName(), null);
}
dist.put("START", 0D);
Node curNode = dMap.getStartNode(), temp = null;
while (!unevaluated.isEmpty()) {
Iterator<Node> it = unevaluated.iterator();
curNode = it.next();
while (it.hasNext()) {
temp = it.next();
if (dist.get(temp.getName()) < dist.get(curNode.getName())) curNode = temp;
}
evaluated.add(curNode);
unevaluated.remove(curNode);
if (dist.get(curNode.getName()) == Double.MAX_VALUE || dMap.getEndNode().equals(curNode))
break;
for (int i = 0; i < curNode.getNumDepend(); i++) {
Node depend = curNode.getDepend(i);
if (evaluated.contains(depend)) continue;
double tempWeight =
dist.get(curNode.getName())
+ dMap.getPath(curNode.getName(), depend.getName()).getWeight();
if (tempWeight < dist.get(depend.getName())) {
dist.put(depend.getName(), tempWeight);
previous.put(depend.getName(), curNode.getName());
}
}
}
p.setWeight(dist.get(curNode.getName()));
String name = curNode.getName();
while (previous.get(curNode.getName()) != null) {
curNode = dMap.getFromName(previous.get(curNode.getName()));
name = curNode.getName() + "," + name;
}
p.setPath(name);
return p;
}
public MapRunner() {
Scanner scan = new Scanner(System.in);
String fileName = scan.next();
if (fileName.equals("rGen")) {
int numNodes = scan.nextInt();
generateRandom(numNodes);
}
scan.close();
readFile(fileName);
if (map == null) throw new NullPointerException();
Timer timer = new Timer();
// Set up brute force map before we do anything to map
Map bruteMap = map.newInstance();
// Dijkstra's Algorithm
timer.start();
System.out.println("DIJKSTRA'S: " + dijkstra());
timer.printMicro();
// Actually do the algorithm here
timer.start();
System.out.println("MY ALGORITHM: " + myAlgorithm());
timer.printMicro();
// Brute force
timer.start();
System.out.println("BRUTE FORCE: " + bruteSearch(bruteMap, bruteMap.getStartNode()));
timer.printMicro();
}