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NthNodeFromEndOfLinkedList.java
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NthNodeFromEndOfLinkedList.java
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import java.util.*;
class Node{
int data;
Node next;
Node(int d)
{
data = d;
next = null;
}
}
public class LinkedList_Element_From_Last{
Node head;
Node tail;
void printList(Node head){
Node temp = head;
while (temp != null){
System.out.print(temp.data+" ");
temp = temp.next;
}
System.out.println();
}
public void addToTheLast(Node node) {
if (head == null) {
head = node;
tail = node;
} else {
tail.next = node;
tail = node;
}
}
public static void main(String args[]){
Scanner sc = new Scanner(System.in);
int t=sc.nextInt();
while(t>0)
{
int n = sc.nextInt();
int k = sc.nextInt();
LinkedList_Element_From_Last llist = new LinkedList_Element_From_Last();
int a1=sc.nextInt();
Node head= new Node(a1);
llist.addToTheLast(head);
for (int i = 1; i < n; i++) {
int a = sc.nextInt();
llist.addToTheLast(new Node(a));
}
GfG g = new GfG();
System.out.println(g.getNthFromLast(llist.head,k));
t--;
}
}
}
class GfG{
int getNthFromLast(Node head, int n){
int length = 0;
Node iterator = head;
while(iterator != null){
iterator = iterator.next;
length++;
}
iterator = head;
int currentPosition = length;
while(iterator != null){
if(currentPosition == n){
return iterator.data;
}
currentPosition--;
iterator = iterator.next;
}
return -1;
}
}
// Implemented using Stack
class GfG1{
int getNthFromLast(Node head, int n){
if(head == null){
return -1;
}
int length = 0;
Node iterator = head;
Stack<Integer> stack = new Stack<Integer>();
while(iterator != null){
stack.push(iterator.data);
iterator = iterator.next;
length++;
}
int value = -1;
while(n > 0 && n <= length){
value = stack.peek();
stack.pop();
n--;
}
return value;
}
}