package com.coding.basic;
public class Stack {
private ArrayList elementData = new ArrayList();
public void push(Object o){
this.elementData.add(o);
}
public Object pop(){
return this.elementData.remove(this.elementData.size()-1);
}
public Object peek(){
return this.elementData.get(this.elementData.size()-1);
}
public boolean isEmpty(){
if(this.elementData.size() == 0){
return true;
}else{
return false;
}
}
public int size(){
return this.elementData.size();
}
public String toString(){
return this.elementData.toString();
}
}