// $xId: Waiting.java,v 1.2 2000-06-25 19:25:19+09 kaiya Exp kaiya $

import java.util.*;

class Waiting{
private Random r;
    Waiting(){
        r=new Random();
    }
    void wait(Thread t){
        int w=r.nextInt(); w=(w>0? w: w*(-1))%500;
        try{
            t.sleep(w);
        }catch(InterruptedException e){
        }
    }
}