in the linked list implementation of the stack code example

Example 1: Linked List implementation

public class LinkedList {

    private Node head;
    private int length = 0;

    public LinkedList() {
        this.head = new Node(null);
    }

    public int size() {
        return length;
    }


     // Adds an element to the end of the list
    public void add(Object data)  {

        Node node = new Node(data);
        Node iterator = head;
        while (iterator.getNext() != null){
            iterator = iterator.getNext();
        }
        iterator.setNext(node);
        length++;
    }


     // Obtains an element by index
    public Object get(int index) {

        if (head.getNext() == null || index >= length){
            return null;
        }

        Node iterator = head.getNext();
        int counter = 0;

        while(counter < index){

            iterator = iterator.getNext();
            counter++;
        }
        return iterator.getData();

    }


     // Returns the index of the element in the list
    public int indexOf(Object data) {
        Node obj=head;
        for (int i = 0; i < length; i++) {
            obj = obj.getNext();
            if (obj.getData().equals(data)) {
                return i;
            }
        }
        return -1;
        //throw new Exception("Data not found");
    }


     // Removes an element from the list
    public boolean remove(Object data) {

        if (head.getNext() == null){
            return false;
        }

        Node iterator = head;

        while(iterator.getNext() != null){

            if (iterator.getNext().getData().equals(data)){
                iterator.setNext(iterator.getNext().getNext());
                length--;
                return true;
            }

            iterator = iterator.getNext();
        }

        return false;
    }

    private class Node {

        private Object data;
        private Node next;

        public Node(Object data) {
            this.data = data;
            next = null;
        }

        public Object getData() {
            return data;
        }

        public void setData(Object data) {
            this.data = data;
        }

        public Node getNext() {
            return next;
        }

        public void setNext(Node next) {
            this.next = next;
        }
    }

}

Example 2: stack implementation using linked list in c

/*
 * C Program to Implement a Stack using Linked List
 */
#include <stdio.h>
#include <stdlib.h>
 
struct node
{
    int info;
    struct node *ptr;
}*top,*top1,*temp;
 
int topelement();
void push(int data);
void pop();
void empty();
void display();
void destroy();
void stack_count();
void create();
 
int count = 0;
 
void main()
{
    int no, ch, e;
 
    printf("\n 1 - Push");
    printf("\n 2 - Pop");
    printf("\n 3 - Top");
    printf("\n 4 - Empty");
    printf("\n 5 - Exit");
    printf("\n 6 - Dipslay");
    printf("\n 7 - Stack Count");
    printf("\n 8 - Destroy stack");
 
    create();
 
    while (1)
    {
        printf("\n Enter choice : ");
        scanf("%d", &ch);
 
        switch (ch)
        {
        case 1:
            printf("Enter data : ");
            scanf("%d", &no);
            push(no);
            break;
        case 2:
            pop();
            break;
        case 3:
            if (top == NULL)
                printf("No elements in stack");
            else
            {
                e = topelement();
                printf("\n Top element : %d", e);
            }
            break;
        case 4:
            empty();
            break;
        case 5:
            exit(0);
        case 6:
            display();
            break;
        case 7:
            stack_count();
            break;
        case 8:
            destroy();
            break;
        default :
            printf(" Wrong choice, Please enter correct choice  ");
            break;
        }
    }
}
 
/* Create empty stack */
void create()
{
    top = NULL;
}
 
/* Count stack elements */
void stack_count()
{
    printf("\n No. of elements in stack : %d", count);
}
 
/* Push data into stack */
void push(int data)
{
    if (top == NULL)
    {
        top =(struct node *)malloc(1*sizeof(struct node));
        top->ptr = NULL;
        top->info = data;
    }
    else
    {
        temp =(struct node *)malloc(1*sizeof(struct node));
        temp->ptr = top;
        temp->info = data;
        top = temp;
    }
    count++;
}
 
/* Display stack elements */
void display()
{
    top1 = top;
 
    if (top1 == NULL)
    {
        printf("Stack is empty");
        return;
    }
 
    while (top1 != NULL)
    {
        printf("%d ", top1->info);
        top1 = top1->ptr;
    }
 }
 
/* Pop Operation on stack */
void pop()
{
    top1 = top;
 
    if (top1 == NULL)
    {
        printf("\n Error : Trying to pop from empty stack");
        return;
    }
    else
        top1 = top1->ptr;
    printf("\n Popped value : %d", top->info);
    free(top);
    top = top1;
    count--;
}
 
/* Return top element */
int topelement()
{
    return(top->info);
}
 
/* Check if stack is empty or not */
void empty()
{
    if (top == NULL)
        printf("\n Stack is empty");
    else
        printf("\n Stack is not empty with %d elements", count);
}
 
/* Destroy entire stack */
void destroy()
{
    top1 = top;
 
    while (top1 != NULL)
    {
        top1 = top->ptr;
        free(top);
        top = top1;
        top1 = top1->ptr;
    }
    free(top1);
    top = NULL;
 
    printf("\n All stack elements destroyed");
    count = 0;
}