function ocultamenu(){
for(i=1; i<50; i++){
	xobj = document.getElementById("sub_"+i);
	if (xobj != null){
		xobj.style.display = "none";
	}
}
}
function despliega(xsubmenu){
	ocultamenu();
  var menu = document.getElementById(xsubmenu);
    if(menu.style.display == "none"){
	menu.style.display = "block";
    }
    else{
      menu.style.display = "none";
    }
}