LinkedList remove() Method in Java
LinkedList as we all know is a way of storing data that contains sets of nodes where each node contains data and address part where address part is responsible for linking of nodes and hence forming a List over which now we can perform operations. Now here we want to remove a node/s using the remove() method of LinkedList class only.
Illustration:
Types of remove() method present inside this class:
- With no arguments inside
- Passing index as in arguments
- Passing object as in arguments
let us discuss each of them alongside implementing by providing a clean java program which is as follows:
Type 1: remove() Method
It is used to remove an element from a linked list. The element is removed from the beginning or head of the linked list.
Syntax:
LinkedList.remove()
Parameters: This function does not take any parameter.
Return Value: This method returns the head of the list or the element present at the head of the list.
Example:
Java
// Java Program to Illustrate remove() method// of LinkedList class// Default removal from the last of List// Importing required classesimport java.io.*;import java.util.LinkedList;// Main classpublic class GFG { // Main driver method public static void main(String args[]) { // Creating an empty LinkedList of String type LinkedList<String> list = new LinkedList<String>(); // Adding elements in the list // Using add() method list.add("Geeks"); list.add("for"); list.add("Geeks"); list.add("10"); list.add("20"); // Printing the elements inside LinkedList System.out.println("LinkedList:" + list); // Removing the head from List // using remove() method list.remove(); // Printing the final elements inside Linkedlist System.out.println("Final LinkedList:" + list); }} |
LinkedList:[Geeks, for, Geeks, 10, 20] Final LinkedList:[for, Geeks, 10, 20]
Time Complexity: O(n)
Auxiliary Space: O(n)
Type 2: remove(int index) Method
It is used to remove an element from a linked list from a specific position or index.
Syntax:
LinkedList.remove(int index)
Parameters: The parameter index is of integer data type and specifies the position of the element to be removed from the LinkedList.
Return Value: The element that has just been removed from the list.
Example
Java
// Java Program to Illustrate remove() when position of// element is passed as parameterimport 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>(); // Use add() method to add elements in the list list.add("Geeks"); list.add("for"); list.add("Geeks"); list.add("10"); list.add("20"); // Output the list System.out.println("LinkedList:" + list); // Remove the head using remove() list.remove(4); // Print the final list System.out.println("Final LinkedList:" + list); }} |
LinkedList:[Geeks, for, Geeks, 10, 20] Final LinkedList:[Geeks, for, Geeks, 10]
Time Complexity: O(n)
Auxiliary Space: O(n)
Type 3: remove(Object O) Method
It is used to remove any particular element from the linked list.
Syntax:
LinkedList.remove(Object O)
Parameters: The parameter O is of the object type of linked list and specifies the element to be removed from the list.
Return Value: Returns true if the specified element is found in the list.
Example
Java
// Java Program to Illustrate remove() method// Importing required classesimport java.io.*;import java.util.LinkedList;// Main classpublic class GFG { // Main driver method public static void main(String args[]) { // Creating an empty LinkedList of string type LinkedList<String> list = new LinkedList<String>(); // Adding elements in the list // using add() method list.add("Geeks"); list.add("for"); list.add("Geeks"); list.add("10"); list.add("20"); // Printing the elements before removal // inside above created LinkedList object System.out.println("LinkedList:" + list); // Removing the head // using remove() method list.remove("Geeks"); list.remove("20"); // Printing the final elements after removal // inside above LinkedList object System.out.println("Final LinkedList:" + list); }} |
LinkedList:[Geeks, for, Geeks, 10, 20] Final LinkedList:[for, Geeks, 10]
Time complexity : O(n)
Auxiliary Space : O(n)
