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Java Collection, PriorityQueue Exercises: Retrieve and remove the first element

Java Collection, PriorityQueue Exercises: Exercise-9 with Solution

Write a Java program to retrieve and remove the first element.

Sample Solution:-

Java Code:

import java.util.PriorityQueue;

  public class Exercise9 {
  public static void main(String[] args) {
   // Create Priority Queue
      PriorityQueue<Integer> pq1 = new PriorityQueue<Integer>();  
      PriorityQueue<Integer> pq2 = new PriorityQueue<Integer>();     
   // Add numbers in the Priority Queue
   pq1.add(10);
   pq1.add(22);
   pq1.add(36);
   pq1.add(25);
   pq1.add(16);
   pq1.add(70);
   pq1.add(82);
   pq1.add(89);
   pq1.add(14);
   System.out.println("Original Priority Queue: "+pq1);
   System.out.println("Removes the first element: "+pq1.poll());
   System.out.println("Priority Queue after removing first element: "+pq1);
   }    
}

Sample Output:

Original Priority Queue: [10, 14, 36, 16, 22, 70, 82, 89, 25]          
Removes the first element: 10                                          
Priority Queue after removing first element: [14, 16, 36, 25, 22, 70, 8
2, 89] 

Java Code Editor:

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