var n = 7;
var f = false;
var ru = new Array;
var en = new Array;
var lv = new Array;

function prel_ru(){

   	if(document.images) {
	  for(i=1;i<=n;i++)
               { str = '/buttons/ru' + i + '_o.gif';		
			   ru[i-1] = new Image();
               ru[i-1].src = str;			   
}f = true;
 		}
}
function on_ru(im){
	if (document.images && (f == true)) 
		{document.images[im].src="/buttons/"+im+"_o.gif";}
		
		
}
function off_ru(im){
	if (document.images && (f == true))
		{document.images[im].src = "/buttons/"+im+".gif";}
	
}

function prel_en(){

   	if(document.images) {
	  for(i=1;i<=n;i++)
               { str = '/buttons/en' + i + '_o.gif';		
			   en[i-1] = new Image();
               en[i-1].src = str;			   
}f = true;
 		}
}
function on_en(im){
	if (document.images && (f == true)) 
		{document.images[im].src="/buttons/"+im+"_o.gif";}
		
		
}
function off_en(im){
	if (document.images && (f == true))
		{document.images[im].src = "/buttons/"+im+".gif";}
	
}

function prel_lv(){

   	if(document.images) {
	  for(i=1;i<=n;i++)
               { str = '/buttons/lv' + i + '_o.gif';		
			   lv[i-1] = new Image();
               lv[i-1].src = str;			   
}f = true;
 		}
}
function on_lv(im){
	if (document.images && (f == true)) 
		{document.images[im].src="/buttons/"+im+"_o.gif";}
		
		
}
function off_lv(im){
	if (document.images && (f == true))
		{document.images[im].src = "/buttons/"+im+".gif";}
	
}