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Java Collection, LinkedList Exercises: Retrieve but does not remove, the first element of a linked list

Java Collection, LinkedList Exercises: Exercise-20 with Solution

Write a Java program to retrieve but does not remove, the first element of a linked list.

Sample Solution:-

Java Code:

import java.util.*;

public class Exercise20 {
 public static void main(String[] args) {
  // create an empty linked list
  LinkedList <String> c1 = new LinkedList <String> ();
            c1.add("Red");
          c1.add("Green");
          c1.add("Black");
          c1.add("White");
          c1.add("Pink");
          System.out.println("Original linked list: " + c1); 
     // Retrieve but does not remove, the first element of a linked list
    String x = c1.peekFirst();
    System.out.println("First element in the list: " + x);
    System.out.println("Original linked list: " + c1);   
 }
} 

Sample Output:

Original linked list: [Red, Green, Black, White, Pink]                 
First element in the list: Red                                         
Original linked list: [Red, Green, Black, White, Pink]

Pictorial Presentation:

Java Collection Linked-list: Retrieve but does not remove, the first element of a linked list.

Flowchart:

Flowchart: Retrieve but does not remove, the first element of a linked list

Java Code Editor:

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Java: Tips of the Day

getEnumMap

Converts to enum to Map where key is the name and value is Enum itself.

public static <E extends Enum<E>> Map<String, E> getEnumMap(final Class<E> enumClass) {
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Ref: https://bit.ly/3xXcFZt