after lecture

src/main/java/graphs/ShortestPath.java

@@ -12,28 +12,26 @@ import java.util.Stack;
  */
 public class ShortestPath {
 
-    public static <V> HashMap<V,Integer> search(WeightedGraph<V, Integer> graph, V start) {
-    	HashMap<V,Integer> distances = new HashMap<>();
-    	PriorityQueue<Pair<V>> toSearch = new PriorityQueue<>();
+    public static <V> HashMap<V,Integer> search(WeightedGraph<V, Integer> graph, V start) { //O(n + m log m )
+    	HashMap<V,Integer> distances = new HashMap<>();			//O(1)
+    	PriorityQueue<Pair<V>> toSearch = new PriorityQueue<>();//O(1)
     	
     	//add start node
-    	toSearch.add(new Pair<V>(start, 0));
+    	toSearch.add(new Pair<V>(start, 0));					//O(1)
     	
-    	while(!toSearch.isEmpty()) {
-    		Pair<V> best = toSearch.remove();
+    	while(!toSearch.isEmpty()) { //O(m) times
+    		Pair<V> best = toSearch.remove(); //m times O(log m)
 
-    		if(distances.containsKey(best.getVetrex()))
+    		if(distances.containsKey(best.getVertex())) //O(1)*m = O(m)
     			continue;
-    		else {
-    			distances.put(best.getVetrex(), best.getDistance());
-    			for(V neighbour : graph.neighbours(best.getVetrex())) {
-    				int weight = best.getDistance()+graph.getWeight(best.getVetrex(),neighbour);
-    				toSearch.add(new Pair<V>(neighbour, weight));
+    		else { //n times  O(n + m*log m)
+    			distances.put(best.getVertex(), best.getDistance()); //O(1)
+    			for(V neighbour : graph.neighbours(best.getVertex())) { //2m times   sum av gradtall til hver node er 2m
+    				int weight = best.getDistance()+graph.getWeight(best.getVertex(),neighbour); //O(1)
+    				toSearch.add(new Pair<V>(neighbour, weight)); //O(log m)
     			}
-    		}
-    			
+    		}    			
     	}
-    	
     	return distances;
     }
 }
@@ -47,7 +45,7 @@ class Pair<V> implements Comparable<Pair<V>>{
 		this.distance = distance;
 	}
 	
-	V getVetrex() {
+	V getVertex() {
 		return vertex;
 	}