var arr=new Array();
var arr2=new Array();
arr[0]='images/dis1.jpg';
arr[1]='images/dis2.jpg';
arr[2]='images/dis3.jpg';
arr[3]='images/dis4.jpg';

arr2[0]='blue'; 
arr2[1]='orange'; 
arr2[2]='pixabella'; 
arr2[3]='clouds';


function scroll_left(){

 if(document.services.chnum.value>0){
	document.getElementById('strr').style.visibility='visible'; 

	 ch=parseInt(document.services.chnum.value)-1;
	 document.getElementById('smi1').innerHTML='<img border=0 height=62 src='+arr[ch]+'>';
	 document.getElementById('smi2').innerHTML='<img border=0 height=62 src='+arr[ch+1]+'>';
	 document.getElementById('smi3').innerHTML='<img border=0 height=62 src='+arr[ch+2]+'>';
	 document.services.chnum.value=ch;
 } 
 if(ch==0) document.getElementById('strl').style.visibility='hidden'; 
}

function scroll_right(){

 if(document.services.chnum.value<arr2.length-3){


	document.getElementById('strl').style.visibility='visible'; 

	 ch=parseInt(document.services.chnum.value)+1;
	 document.getElementById('smi1').innerHTML='<img border=0 height=62 src='+arr[ch]+'>';
	 document.getElementById('smi2').innerHTML='<img border=0 height=62 src='+arr[ch+1]+'>';
	 document.getElementById('smi3').innerHTML='<img border=0 height=62 src='+arr[ch+2]+'>';

	 document.services.chnum.value=ch;
 }
 if(ch==(arr2.length-3)) document.getElementById('strr').style.visibility='hidden'; 
}