function h_v(n) {
 for (i=1;i<N;i++) {
  obj=document.getElementById("id"+i);
  img=document.getElementById("img"+i);
  if (n==i && obj.style.display=="none") {
   document.cookie="c"+n+"="+0;
   obj.style.display="block";
   img.src="images/m1.gif";
  } else {
   document.cookie="c"+n+"="+1;
   obj.style.display="none";
   img.src="images/m2.gif";
  }
 }
}