feat: add PriorityQueueBasedOnNaturalOrdering demonstrating Java PriorityQueue behavior

Implemented PriorityQueueBasedOnNaturalOrdering.java to showcase natural ordering
(min-heap) behavior of PriorityQueue. Demonstrates insertion, polling, and iteration
order, explaining that elements are ordered by natural order (lowest first for numbers)
and can be customized using comparators. Includes notes on internal heap structure
and O(log n) insertion complexity.

Signed-off-by: https://github.com/Someshdiwan <[email protected]>

Author: Someshdiwan

Section 25 Collections Frameworks/Queue Interface/Priority Queue/src/PriorityQueueBasedOnNaturalOrdering.java

@@ -2,12 +2,15 @@
 
 public class PriorityQueueBasedOnNaturalOrdering {
     public static void main(String[] args) {
-        // part of the Queue interface
-        // orders elements based on their natural ordering (for primitives lowest first)
-        // custom comparator for customised ordering
-        // does not allow null elements
+        /*
+        part of the Queue interface
+        orders elements based on their natural ordering (for primitives lowest first)
+        custom comparator for customized ordering
+        does not allow null elements
+        */
         PriorityQueue<Integer> pq = new PriorityQueue<>();
 
+        // We can use if we don't need natural ordering of elements, Custom comparator.
         //PriorityQueue<Integer> pq = new PriorityQueue<>((x,y)->x-y);
 
         pq.add(15);
@@ -16,14 +19,17 @@ public static void main(String[] args) {
         pq.add(5);
         System.out.println(pq); // not sorted
 
-        //Queue Retrieves and removes the head of this queue, or returns null if this queue is empty.
+        // System.out.println(pq.); // Check methods inside Queue.
+
+        //Queue Retrieves and removes the head of this queue or returns null if this queue is empty.
         while (!pq.isEmpty()) {
             System.out.println(pq.poll());
         }
-        /* internal working:
 
+        /*
+        internal working:
         PriorityQueue is implemented as a min-heap by default (for natural ordering).
         Time complexity of min-heap inserting an element is O(Log n).
         */
     }
-}
+}