Description

Linked List representation of stack is difficult to implement but there is no need to declare the size before.
Addition and deletion of node from stack can be done on node pointed by TOP.
Here all three operation like push, pop and peek can be performed.
1)PUSH : PUSH operation is used to insert node into the stack.
    case 1 :  If stack do not have any node
              Make the new node as first node and top will point to this new    node.
    case 2 :  If stack has node
              Make the new node as first node of stack by adding address of top to the next field of new
 node and assigning the address of new node to top.
2) POP : POP operation is used to delete node from stack
    case 1 : If stack do not have node
             Show message stack underflow
    case 2 : If stack has node
         The node pointed by top will be deleted and top will point to node next to node pointed by top.
3) PEEK : PEEK operation does not insert or delete any node to stack.
    case 1 : If stack do not have node
         Show message stack underflow
    case 2 : If stack has node
         Show the node pointed by top.

C/C++

#include<stdio.h>
#include<malloc.h>

void *push();
void *pop();
void *peek();
void *display();

//Declaring nodes for stack
struct stack{
    int data;
    struct stack *next;
};

struct stack *top = NULL;

int main(){
    int option;

    do{
        printf("\nWhich operation you want to perform : ");
        printf("\n1.PUSH\n2.POP\n3.PEEK\n4.DISPLAY\n5.EXIT : \n");
        scanf("%d",&option);
        switch(option){
        case 1:
            push();
            break;
        case 2:
            pop();
            break;
        case 3:
            peek();
            break;
        case 4:
            display();
            break;
        case 5:
            break;
        default:
            printf("Enter Valid Input");
        }
    }while(option!=5);

    return 0;
}

void *push(){
    int val;
    printf("Enter the value to be added to stack : ");
    scanf("%d",&val);

    //Creating new node
    struct stack *newNode = (struct stack *)malloc(sizeof(struct stack));
    newNode->data = val;

    //If stack has no any element
    if(top==NULL){
        newNode->next=NULL;
        top=newNode;
    }else{
        //If stack has few elements
        newNode->next=top;
        top=newNode;
    }
}

void *pop(){

    struct stack *temp;

    //If stack is empty
    if(top==NULL){
        printf("Stack Underflow");
    }else{
        //If stack has elements
        temp=top;
        top=top->next;
        printf("The poped value is : %d",temp->data);
        free(temp);
    }
}

//In peek operation stack return the top element without deleting any element
void *peek(){
    //if stack is empty
    if(top==NULL){
        printf("Stack Underflow");
    }else{
        //If stack has elements
        printf("The peek value is : %d",top->data);
    }
}

//It display the elements of stack
void *display(){
    //If stack is empty
    if(top==NULL){
        printf("Stack Underflow");
    }else{
        //If stack has elements then show from top
        struct stack *temp = top;
        printf("The elements of stack : ");
        while(temp!=NULL){
            printf("%d ",temp->data);
            temp=temp->next;
        }
    }
}

Output

Java

import java.io.*;
import java.util.Scanner;

public class LinkedListImplStack {
    
    //Declaring nodes for stack
    static class Stack{
        int data;
        Stack next;
        
        public Stack(int data) {
            this.data = data;
            this.next = null;
        }
    }
    
    public static Stack top = null;
    
    static Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) {
        int option;

        do {
            System.out.println("\nWhich operation you want to perform : ");
            System.out.println("1.PUSH\n2.POP\n3.PEEK\n4.DISPLAY\n5.EXIT : ");
            option = scanner.nextInt();
            switch (option) {
            case 1:
                push();
                break;
            case 2:
                pop();
                break;
            case 3:
                peek();
                break;
            case 4:
                display();
                break;
            case 5:
                System.out.println("Program terminated");
                break;
            default:
                System.out.println("Enter Valid Input");
            }
        } while(option!=5);
    }

    //It display the elements of stack
    private static void display() {
        //If stack is empty
        if (top == null) {
            System.out.println("**Stack is empty**");
        } else {
            //If stack has elements then show from top
            Stack temp = top;
            System.out.println("The elements of stack : ");
            while(temp!=null){
                System.out.print(temp.data+" ");
                temp=temp.next;
            }
        }
    }
    //In peek operation stack return the top element without deleting any element
    private static void peek() {
        //if stack is empty
        if(top==null){
            System.out.println("Stack Underflow");
        }else{
        	//If stack has elements
            System.out.println("The peek value is : "+top.data);
        }
    }

    private static void pop() {
        Stack temp;
        //If stack is empty
        if(top==null){
            System.out.println("Stack Underflow");
        }else{
        	//If stack has elements
            temp=top;
            top=top.next;
            System.out.println("The poped value is : "+temp.data);
        }
    }

    private static void push() {
        int val;
        System.out.println("Enter the value to be added to stack : ");
        val = scanner.nextInt();

        //Creating new node
        Stack newNode = new Stack(val);

        //If stack has no any element
        if(top==null){
            newNode.next=null;
            top=newNode;
        }else{
        	//If stack has few elements
            newNode.next=top;
            top=newNode;
        }
    }
}

Output

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