Trees: PrintNaryTreeWithLevels minor refactoring.

rpanjrath · rpanjrath · commit fe7e8f09631a · 2014-02-03T23:23:51.000-08:00
diff --git a/src/trees/leftviewofatree/LeftViewOfATree.java b/src/trees/leftviewofatree/LeftViewOfATree.java
@@ -23,7 +23,7 @@ public static void bfs(Graph graph) {
         vertex.setVisited(true);
         System.out.println(vertex);
         queue.add(vertex);
-        //null acts as a pointer/marker when new level should begin.
+        //dummy acts as a pointer/marker when new level should begin.
         Vertex dummy = new Vertex("dummy");
         queue.add(dummy);
         while (!queue.isEmpty()) {
diff --git a/src/trees/printnarytreewithlevels/PrintNaryTreeWithLevels.java b/src/trees/printnarytreewithlevels/PrintNaryTreeWithLevels.java
@@ -31,17 +31,18 @@ public static void bfs(Graph graph) {
         System.out.println(vertex + "level " + counter);
         counter++;
         queue.add(vertex);
-        //null acts as a pointer/marker when new level should begin.
-        queue.add(null);
+        //dummy acts as a pointer/marker when new level should begin.
+        Vertex dummy = new Vertex("dummy");
+        queue.add(dummy);
         while (!queue.isEmpty()) {
             Vertex currentVertex = queue.remove();
-            if (currentVertex == null) {
+            if (currentVertex == dummy) {
                 counter++;
                 if (queue.isEmpty()) {
                     break;
                 }
                 currentVertex = queue.remove();
-                queue.add(null);
+                queue.add(dummy);
             }
             Vertex unvisitedVertex;
             while ((unvisitedVertex = getUnvisitedVertex(currentVertex)) != null) {
