public class PingPong extends Thread{
    String word;
    int delay;
    /**
     * Constructor.
     */
    public PingPong (String w,int d) {
    word=w;
    delay=d;
    }

    public void run() {
	int j;
        try{ for (j=1;j<10;j=j+1) {
                    System.out.print(word+" ");
                    sleep(delay);
                    }
		    } catch (InterruptedException e) {
		      return;
	    }
	}               



    public static void main(String args[]) {
	new PingPong ("ping",30).start();
	new PingPong ("pong",100).start();
    }
}