// JavaScript Document

function GetTime() { 
var dt = new Date();
var def = dt.getTimezoneOffset()/60;
var gmt = (dt.getHours() + def);
var ending = ":" + IfZero(dt.getMinutes()) + ":" +  IfZero(dt.getSeconds());
document.getElementById("beijing").innerHTML=(IfZero(dt.getHours()) + ":" + IfZero(dt.getMinutes()) + ":" + IfZero(dt.getSeconds()));
var east =check24(((gmt + (24-5)) > 24) ? ((gmt + (24-5)) - 24) : (gmt + (24-5)));
document.getElementById("newyork").innerHTML= (IfZero(east) + ending);

var _GMT =check24(((gmt) > 24) ? ((gmt) - 24) : (gmt));
document.getElementById("london").innerHTML = (IfZero(_GMT) + ":" + IfZero(dt.getMinutes())+ ":" + IfZero(dt.getSeconds()));

setTimeout("GetTime()", 1000);
}

function IfZero(num) {
return ((num <= 9) ? ("0" + num) : num);
}

function check24(hour) {
return (hour >= 24) ? hour - 24 : hour;
}

window.onload=GetTime;