function cmenu(nr, ar){
  for ( i=1; i<10; i++){
    if ( i != nr ){
      document.getElementById("mmenubox"+i).style.visibility = "hidden";
      
        document.getElementById("mmenuarr"+i).style.visibility = "hidden";
      
    }
  }
  document.getElementById("mmenubox"+nr).style.visibility = "visible";
  if ( ar == 1){
    document.getElementById("mmenuarr"+nr).style.visibility = "visible";
  }
}