function clock(){
       var nowtime=new Date();
       var hours=nowtime.getHours();
       
       hours=hours>9?hours:"0"+hours;
       var minutes=nowtime.getMinutes();
       minutes=minutes>9?minutes:"0"+minutes;
       var seconds=nowtime.getSeconds();
       seconds=seconds>9?seconds:"0"+seconds;
       var disptime=hours+":"+minutes+":"+seconds+" ";
       document.getElementById("clock").innerHTML=disptime;
       setTimeout("clock()",1000);
   }