import java.util.*;
public class LinkedList {
private class Node {
int data;
Node next;
Node(int data, Node next) {
this.data = data;
this.next = next;
}
}
private Node head;
private Node tail;
private int size;
public LinkedList() {
this.head = null;
this.tail = null;
this.size = 0;
}
public LinkedList(Node head, Node tail, int size) {
this.head = head;
this.tail = tail;
this.size = size;
}
// O(1)
public int size() {
return this.size;
}
// O(1)
public boolean isEmpty() {
return this.size() == 0;
}
// O(1)
public Node getFirst() throws Exception {
if (this.isEmpty()) {
throw new Exception("List is empty.");
}
return this.head;
}
// O(1)
public int getLast() throws Exception {
if (this.isEmpty()) {
throw new Exception("List is empty.");
}
return this.tail.data;
}
// O(N)
public int getAt(int idx) throws Exception {
Node temp = this.getNodeAt(idx);
return temp.data;
}
// O(N)
private Node getNodeAt(int idx) throws Exception {
if (this.isEmpty()) {
throw new Exception("List is empty");
}
if (idx < 0 || idx >= this.size()) {
throw new Exception("Invalid arguments");
}
Node retVal = this.head;
for (int i = 0; i < idx; i++) {
retVal = retVal.next;
}
return retVal;
}
// O(1)
public void addFirst(int data) {
Node node = new Node(data, this.head);
if (this.size() == 0) {
this.head = node;
this.tail = node;
} else {
this.head = node;
}
this.size++;
}
// O(1)
public void addLast(int data) {
Node node = new Node(data, null);
if (this.size() == 0) {
this.head = node;
this.tail = node;
} else {
this.tail.next = node;
this.tail = node;
}
this.size++;
}
// O(n)
public void addAt(int idx, int data) throws Exception {
if (idx < 0 || idx > this.size()) {
throw new Exception("Invalid arguments");
}
if (idx == 0) {
this.addFirst(data);
} else if (idx == this.size()) {
this.addLast(data);
} else {
Node nm1 = this.getNodeAt(idx - 1);
Node n = nm1.next;
Node node = new Node(data, n);
nm1.next = node;
this.size++;
}
}
// O(1)
public int removeFirst() throws Exception {
if (this.isEmpty()) {
throw new Exception("List is empty");
}
int retVal = this.head.data;
if (this.size() == 1) {
this.head = null;
this.tail = null;
} else {
this.head = this.head.next;
}
this.size--;
return retVal;
}
// O(n)
public int removeLast() throws Exception {
if (this.isEmpty()) {
throw new Exception("List is empty");
}
int retVal = this.tail.data;
if (this.size() == 1) {
this.head = null;
this.tail = null;
} else {
Node sm2 = this.getNodeAt(this.size() - 2);
sm2.next = null;
this.tail = sm2;
}
this.size--;
return retVal;
}
// O(n)
public int removeAt(int idx) throws Exception {
if (this.isEmpty()) {
throw new Exception("List is empty");
}
if (idx < 0 || idx >= this.size()) {
throw new Exception("Invalid arguments");
}
if (idx == 0) {
return this.removeFirst();
} else if (idx == this.size() - 1) {
return this.removeLast();
} else {
Node nm1 = this.getNodeAt(idx - 1);
Node n = nm1.next;
Node np1 = n.next;
nm1.next = np1;
this.size--;
return n.data;
}
}
// O(n)
public void display(Node newhead) {
Node node = newhead;
while (node != null) {
System.out.print(node.data + " ");
node = node.next;
}
//System.out.println("END");
}
public Node appendLastN(int k,Node head,int N) throws Exception {
Node current,newhead,prev;
current = head;
prev = head;
int count = 0;
while(count<N-k){
prev = current;
current = current.next;
count++;
}
newhead = current;
while(current.next != null){
current = current.next;
}
current.next = head;
return newhead;
}
public static void main(String[] args) throws Exception {
Scanner scn = new Scanner(System.in);
int N = scn.nextInt();
//int k = scn.nextInt();
LinkedList list = new LinkedList();
for (int i = 0; i < N; i++) {
list.addLast(scn.nextInt());
}
int k= scn.nextInt();
Node head = list.getFirst();
Node newhead = list.appendLastN(k,head,N);
list.display(newhead);
}
}
it is not showing any output kindly help me for the same