/* The class name doesn't have to be Main, as long as the class is not public. */
class Main
{
 
  public static void main (String[] args)
  {
     System.out.println("Hello world!");
     
     if (2 < 3)
     {
        System.out.println("2 is less than 3");
     }
     else
     {
        System.out.println("2 is NOT less than 3");
     }
     
     for (int n = 0; n <= 3; n++)
     {
        double nSquared = Math.pow(n, 2);
        String myMessage = "The number " + n + " squared is " + nSquared;
        System.out.println( myMessage );
     }
     
  }
 
}