Consider the definition of a LinkedIntList class and ListNode class below. Write a method for this class, called everyOther(). This method takes no arguments, but it eliminates every other node in the linked list. For example, if a LinkedList list contains [1, 2, 3, 4, 5], after a the call: list.everyOther(), list contains [1, 3, 5]. If list contains [1, 2, 3, 4], after the call it will contain [1, 3]. If the list contains 0 or 1 elements, the list is unchanged. You are not allowed to assume any other methods are defined on the LinkedIntList class other than the ones defined on the below.

// Class LinkedIntList can be used to store a list of integers.

import java.util.*;

public class LinkedIntList {

// first value in the list

private ListNode front;

// size of list

private int size;

// post: constructs an empty list

public LinkedIntList() {

front = null;

}

// post: returns the current number of elements in the list

public int size() {

return size;

}

// pre : 0 <= index < size()

// post: returns the integer at the given index in the list

public int get(int index) {

return nodeAt(index).data;

}

// post: creates a comma-separated, bracketed version of the list

public String toString() {

// if the list is empty

if (front == null) {

return "[]";

}

// otherwise

String result = "[" + front.data;

ListNode current = front.next;

while (current != null) {

result += ", " + current.data;

current = current.next;

}

result += "]";

return result;

}

// post : returns the position of the first occurrence of the given

// value (-1 if not found)

public int indexOf(int value) {

int index = 0;

ListNode current = front;

while (current != null) {

if (current.data == value) {

return index;

}

index++;

current = current.next;

}

return -1;

}

// post: appends the given value to the end of the list

public void add(int value) {

size++;

// if this is the only node in this list

if (front == null) {

front = new ListNode(value);

return;

}

// otherwise, we need to put the new node at the end of the list

ListNode current = front;

while (current.next != null) {

current = current.next;

}

current.next = new ListNode(value);

}

// pre: 0 <= index <= size()

// post: inserts the given value at the given index

public void add(int index, int value) {

size++;

if (index == 0) {

// put the new node at the front

front = new ListNode(value, front);

} else {

// get the node just this node will link to

ListNode current = nodeAt(index - 1);

current.next = new ListNode(value, current.next);

}

}

// pre : 0 <= index < size()

// post: removes value at the given index

public void remove(int index) {

size--;

// if we are removing the front ndoe

if (index == 0) {

front = front.next;

} else {

// get the node that the node we are removing is linked to

ListNode current = nodeAt(index - 1);

current.next = current.next.next;

}

}

// pre : 0 <= i < size()

// post: returns a reference to the node at the given index

private ListNode nodeAt(int index) {

ListNode current = front;

for (int i = 0; i < index; i++) {

current = current.next;

}

return current;

}

public int deleteBack() {

// Empty list

int nodeData = 0;

if (front == null) {

// throw new NoSuchElementException();

}

// List length 1

else if (front.next == null) {

nodeData = front.data;

remove(0);

}

else {

ListNode current = nodeAt(size - 2);

nodeData = current.next.data;

remove(size - 1);

}

return nodeData;

}

public int lastIndexOf(int value) {

int index = -1;

int position = 0;

ListNode current = front;

if (front != null) {

while (position < size) {

if (current.data == value)

index = position;

position++;

current = current.next;

}

}

return index;

}

}

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// ListNode is a class for storing a single node of a linked

// list. This node class is for a list of integer values.

public class ListNode {

public int data; // data stored in this node

public ListNode next; // link to next node in the list

// Post: constructs a node with data 0 and null link

public ListNode() {

this(0, null);

}

// Parameter: data, the integer value to be stored

// Post: constructs a node with given data and null link

public ListNode(int data) {

this(data, null);

}

// Parameters: data, the integer value to be stored,

// next, the link to set next to

// Post: constructs a node with given data and given link

public ListNode(int data, ListNode next) {

this.data = data;

this.next = next;

}

}