package Stack_Java;

import java.util.*;

public class LinkedListStack { 
      private int top; 
      private LinkedList storage; 
 
      LinkedListStack() { 
            storage = new LinkedList(); 
            top = -1; 
      } 
 
      void push(Object value) { 
            top++; 
            storage.add(value); 
      } 
 
      Object peek() { 
            if (top == -1) 
                  throw new EmptyStackException(); 
            return storage.get(top); 
      } 
 
      Object pop() { 
            if (top == -1) 
                  throw new EmptyStackException(); 
            Object result = storage.get(top);
            storage.remove(top--); 
            return result;
      } 
 
      boolean empty() { 
            return (top == -1); 
      } 
}