function show(num) {
   hide();
   var z = document.getElementById('submenu'+num);
   if (z) {z.style.display='block';}
}

function hide() {
   for (var i = 1; i<=8; i++) {
      if (document.getElementById('submenu'+i)) {
         document.getElementById('submenu'+i).style.display='none';
      }
   }
}