/**
 * Array example
 **/
public class Alist {
  Object[] elements = new Object[10];
  int size = 0;

  public String toString() {
    StringBuilder sb = new StringBuilder();
    sb.append('[');
    for(int i=0;i<size();i++) {
      if(i > 0) sb.append(',');
      sb.append(get(i));
    }
    sb.append(']');
    return sb.toString();
  }

  public void add(Object t) {
    if(size >= elements.length) {
      final int n = elements.length;
      Object[] newElements = new Object[(int)(elements.length*1.3)];
      for(int i=0;i<size;i++)
        newElements[i] = elements[i];
      elements = newElements;
    }
    elements[size++] = t;
  }

  public int size() {
    return size;
  }

  public void set(int n,Object t) {
    assert n >= 0 && n < size;
    elements[n] = t;
  }

  public Object get(int n) {
    assert n >= 0 && n < size;
    return elements[n];
  }

  public static void main(String[] args) {
    Alist<Integer> al = new Alist<>();
    al.add(3);
    al.add(9);
    al.add(2);
    for(int i=0;i<al.size();i++) {
      System.out.println(al.get(i));
    }
    System.out.println(al);
  }
}