var leftmymar;
var mymar;
var speed=30;
var demo=document.getelementbyid('demo');
var demo1=document.getelementbyid('demo1');
var demo2=document.getelementbyid('demo2');
function marqueeleft()
{
clearinterval(mymar)


demo2.innerhtml=demo1.innerhtml
//向左走
function marquee(){
if(demo2.offsetwidth-demo.scrollleft<=0)
demo.scrollleft-=demo1.offsetwidth
else{
demo.scrollleft++
}
}
leftmymar=setinterval(marquee,speed)
demo.onmouseover=function() {clearinterval(leftmymar)}
demo.onmouseout=function() {leftmymar=setinterval(marquee,speed)}
}
marqueeleft();

function marqueeright()
{
clearinterval(leftmymar)

demo2.innerhtml=demo1.innerhtml

demo.scrollleft=demo.scrollwidth 
function marquee(){ 
if(demo.scrollleft<=0) 
demo.scrollleft+=demo2.offsetwidth 
else{ 
demo.scrollleft-- 
} 
} 
mymar=setinterval(marquee,speed)
demo.onmouseover=function() {clearinterval(mymar)}
demo.onmouseout=function() {mymar=setinterval(marquee,speed)}
}