Fix Queue using ArrayList

Author: bcExpt1123

src/main/java/org/alda/structure/queue/Queue.java

@@ -42,7 +42,7 @@ public T dequeue() {
         if (items.isEmpty()) {
             return null;
         }
-        return items.removeLast();
+        return items.removeFirst();
     }
 
     /**

src/main/java/org/alda/structure/queue/array/QueueArray.java

@@ -44,7 +44,7 @@ public T dequeue() {
         if (items.isEmpty()) {
             return null;
         }
-        return items.removeLast();
+        return items.removeFirst();
     }
 
     /**