tugas2.java

// Online Java Compiler
// Use this editor to write, compile and run your Java code online
import java.util.Scanner;

class LLStack {
    class Node {
        public String data;
        public Node next;
    }
    
    private Node first;
    
    public LLStack() {
        first = null;
    }
    
    public void push(String data) {
        Node n = new Node();
        n.data=data;
        n.next=first;
        first=n;
    }
    
    public String peek() {
        if(first==null) {
            return null;
        }
        
        String result = first.data;
        return result;
    }
    
    public String pop() {
         if(first==null) {
            return null;
        }
        
        Node temp = first;
        first = first.next;
        return temp.data;
    }
}

class HelloWorld {
    public static void main(String[] args) {
        Scanner myScanner = new Scanner(System.in);
        LLStack list = new LLStack();
        
        for(int i=0; i<5;i++) {
            System.out.print("Input barang ke-"+(i+1)+": ");
            String name = myScanner.nextLine();
            
            list.push(name);
        }
        
        System.out.println("First peek: "+list.peek());
        System.out.println("First pop: "+list.pop());
        System.out.println("Second pop: "+list.pop());
    }
    
    
}