package com.coding.basic;
public class MyStack {
private MyArrayList elementData = new MyArrayList();
public void push(Object o) {
elementData.add(o);
}
public Object pop() {
if (elementData.size() > 0) {
Object data = elementData.get(elementData.size() - 1);
elementData.remove(elementData.size() - 1);
return data;
}
return null;
}
public Object peek() {
if (elementData.size() > 0) {
return elementData.get(elementData.size() - 1);
}
return null;
}
public boolean isEmpty() {
return elementData.size() == 0;
}
public int size() {
return elementData.size();
}
}