public class HelloWorld
{
  // arguments are passed using the text field below this editor
  public static void main(String[] args)
  {
   Konto klaus = new Konto("Peter Klaus", 1337);

   System.out.println(klaus);
   klaus.einzahlen(20000);
   System.out.println(klaus);
   klaus.inhaber = "Petra Klaus";
   System.out.println(klaus);
   klaus.abheben(1500);
   System.out.println(klaus);
  /*
    Error:
    klaus.nr = 1;
   */
   try{
       klaus.kontoStand = (int) 1e6;
   }catch(Exception a){
       System.out.println("Can't change Money");
   }


   System.out.println(klaus);

  }

  public static class Konto {
      public String inhaber;
      protected int kontoStand;
      public final int nr;

      public Konto(String inhaber, int nr)
      {
        this.kontoStand = 0;
        this.inhaber = inhaber;
        this.nr = nr;
      }

      public void einzahlen(int a){
          kontoStand += a;
      }

      public void abheben(int a){
          kontoStand -= a;
      }


      public String toString()
      {
        return inhaber+" hat "+ kontoStand+" euro. Nr.: "+ nr;
      }
    }
}