package com.coding.basic;
public class Stack {
private ArrayList elementData = new ArrayList();
private int size;
public void push(Object o){
elementData.add(o);
size++;
}
public Object pop(){
return elementData.get(size-1);
}
public Object peek(){
elementData.remove(size--);
return elementData;
}
public boolean isEmpty(){
return size==0;
}
public int size(){
return size;
}
public static void main(String args[]){
Stack s = new Stack();
s.push("1");
s.push("2");
s.push("3");
s.push("4");
System.out.println(s.pop());
s.peek();
for(int i =0;i<s.size();i++){
System.out.println(s.elementData.get(i));}
}
}