function show_menu(arg) {

   if(arg == 20040) {
       var list = document.getElementById("menu_20040");
       list.style.display == "block" ? list.style.display = "none" : list.style.display = "block";
   }

   for(var i=20044;i<20049;i++){
       var list = document.getElementById("menu_"+[i]);
       if(list.length!=0 && i == arg) {
       list.style.display == "block" ? list.style.display = "none" : list.style.display = "block";
       } else if(list.length!=0 && i != arg) {
       list.style.display = "none";
           if(arg != 20040){
               document.getElementById("menu_20040").style.display = "none";
           }
       } else {
       break;
       }
   }

}