In Java, the LinkedList class provides the removeFirst() method to remove and return the first element of the list. If the list is empty, the method throws a NoSuchElementException.
Sure, here is an example of using the removeFirst() method in Java, with the full code and output:
Java
import java.util.LinkedList;public class Example { public static void main(String[] args) { LinkedList<String> list = new LinkedList<>(); // add elements to the list list.add("apple"); list.add("banana"); list.add("orange"); list.add("grape"); System.out.println("Original list:"); System.out.println(list); // remove the first element String removed = list.removeFirst(); System.out.println("Element removed: " + removed); System.out.println(list); }} |
Original list: [apple, banana, orange, grape] Element removed: apple [banana, orange, grape]
In this example, we first create a LinkedList object and add four elements to it. The System.out.println() statement prints the original list to the console.
We then use the removeFirst() method to remove the first element from the list (which is “apple”), and print the removed element and the updated list to the console.
The Java.util.LinkedList.removeFirst() method is used to remove the first element from a linked list. This function also returns the first element after removing it. Syntax:
LinkedList.removeFirst();
Parameters: This function does not take any parameters.
Return Value: The method returns the first element or the element present at the head of the list.
Below program illustrates the Java.util.LinkedList.removeFirst() method:
Java
// Java code to illustrate removeFirst() methodimport java.io.*;import java.util.LinkedList;public class LinkedListDemo { public static void main(String args[]) { // Creating an empty LinkedList LinkedList<String> list = new LinkedList<String>(); // Using add() method to add elements in the list list.add("Geeks"); list.add("for"); list.add("Geeks"); list.add("10"); list.add("20"); // Displaying the list System.out.println("LinkedList:" + list); // Remove the head using removeFirst() method System.out.println("The first element is: " + list.removeFirst()); // Displaying the final list System.out.println("Final LinkedList:" + list); }} |
LinkedList:[Geeks, for, Geeks, 10, 20] The first element is: Geeks Final LinkedList:[for, Geeks, 10, 20]
Example:
Java
// Java code to illustrate removeFirst() methodimport java.io.*;import java.util.LinkedList;public class LinkedListDemo { public static void main(String args[]) { // Creating an empty LinkedList LinkedList<String> list = new LinkedList<String>(); // Using add() method to add elements in the list list.add("Geeks"); list.add("for"); list.add("Geeks"); list.add("10"); list.add("20"); // Displaying the list System.out.println("LinkedList:" + list); // Remove the head using removeFirst() method System.out.println("The first element is: " + list.removeFirst()); // Displaying the final list System.out.println("Final LinkedList:" + list); }} |
LinkedList:[Geeks, for, Geeks, 10, 20] The first element is: Geeks Final LinkedList:[for, Geeks, 10, 20]
