function diapozoom(c)
{
    efface();
 
    image ="photo"+c ;
    document.getElementById("compteur").style.left = parseInt(c)+"px";
    document.getElementById(image).style.visibility='visible';

}

function efface()
{
        d=0;
        image ="photo"+d;
        while (document.getElementById(image))
        {
          document.getElementById(image).style.visibility='hidden';
          d++;
          image ="photo"+d ;
        }
}