import java.util.*;
public class ClearJunk
{
  public static void main (String args [])
  {
      int number;
		String junk;
      Scanner keyboard;
		boolean done;
		
		done = false;
		keyboard = new Scanner (System.in);
		while (!done)
		{
		  try
		  {
		    System.out.println 
		      (" enter a number ");
		    number = keyboard.nextInt();
			 done = true;
			} // end try
		   catch (InputMismatchException ime)
		   {
		      System.out.println 
			     (" what you entered isn't a number ");
			   System.out.print (" try again to ");
		      junk = keyboard.next();
		   }// end catch
		 } // end while
	 }// end main
}// end class