For traversing a linked list in reverse order we can use Descending Iterator or List Iterator
1. Descending Iterator
Syntax:
LinkedList<String> linkedlist = new LinkedList<>(); Iterator<String> listIterator = linkedlist.descendingIterator();
Returns: Descending Iterator returns the Iterator that points to the end of the linked list.
2. List Iterator
Syntax:
LinkedList<String> linkedlist = new LinkedList<>(); ListIterator<String> listIerator = linkedlist.listIterator(linkedlist.size());
Parameter: the size of the linked list, this will make the iterator point at the end of the linked list.
Example 1: Using descending Iterator
Java
// Java program to Iterate a LinkedList in Reverse Order// using descending Iterator import java.util.Iterator;import java.util.LinkedList; public class GFG { public static void main(String[] args) { LinkedList<String> linkedList = new LinkedList<>(); // adding elements to linked list linkedList.add("Geeks"); linkedList.add("For"); linkedList.add("Geek"); linkedList.add("2020"); linkedList.add("2021"); // getting an iterator which points at the // end of the linkedlist Iterator<String> iterator = linkedList.descendingIterator(); // traversing the linkedlist // hasNext() will tell if previous element is // available or not // next() with descending iterator will return the // previous element // and after getting the previous element // is moves the cursor to next previous element. while (iterator.hasNext()) { System.out.println(iterator.next()); } }} |
Output
2021 2020 Geek For Geeks
Example 2: Using List Iterator
Java
// Java program to Iterate a LinkedList in Reverse Order// using List Iterator import java.util.LinkedList;import java.util.ListIterator; public class GFG { public static void main(String[] args) { LinkedList<String> linkedList = new LinkedList<>(); // adding elements of to the linkedlist linkedList.add("Geeks"); linkedList.add("For"); linkedList.add("Geek"); linkedList.add("2020"); linkedList.add("2021"); // getting an iterator that points at the end of the // linkedlist ListIterator<String> listIterator = linkedList.listIterator(linkedList.size()); // Traversing the linked list // hasPrevious() function to check if previous // element is present or not previous() function to // get the previous element and after getting // previous elements it move the cursor to the next // previous element while (listIterator.hasPrevious()) { System.out.println(listIterator.previous()); } }} |
Output
2021 2020 Geek For Geeks
