package com.basic.datastructure;
public class Stack {
private ArrayList elementData = new ArrayList();
private int size;
public void push(Object o){
elementData.add(o);
size++;
}
public Object pop(){
size --;
return elementData.remove(elementData.size() - 1);
}
/**
* Looks at the object at the top of this stack without removing it from the stack.
* @return Object
*/
public Object peek(){
return elementData.get(elementData.size() - 1);
}
public boolean isEmpty(){
return size == 0;
}
public int size(){
return size;
}
public static void main(String[] args) {
Stack stack = new Stack();
for (int i = 0; i < 10; i++) {
stack.push(i);
}
System.out.println(stack.peek());
stack.pop();
System.out.println("Finished");
}
}