var clicked = 19;
  var objCount = 0;
  pic = new Array();
    
    objCount++;
    function preload(name, first, second){
    pic[objCount] = new Array(3);
    pic[objCount][0] = new Image();
    pic[objCount][0].src = first;
    pic[objCount][1] = new Image();
    pic[objCount][1].src = second;
    pic[objCount][2] = name;
    objCount++;
    }
    
    function on(name){
    for (i = 1; i < objCount; i++) {
    if (document.images[pic[i][2]] != null)
    if (name != pic[i][2]){
    if (i != clicked){
    document.images[pic[i][2]].src = pic[i][0].src;
    }else{
    document.images[pic[i][2]].src = pic[i][1].src;
    }
    }else{
    document.images[pic[i][2]].src = pic[i][1].src;
          
        }
      }
    }
    function off(){
    for (i = 1; i < objCount; i++) {
    if (document.images[pic[i][2]] != null)
    if (i != clicked){
    document.images[pic[i][2]].src = pic[i][0].src;
    }else{
    document.images[pic[i][2]].src = pic[i][1].src;
          }
       
       }
    }
    function press(numero){
      clicked=numero;
      off();
    }
    preload("nappula1", "napit/nappi01.gif", "napit/nappi01b.gif");
    preload("nappula2", "napit/nappi02.gif", "napit/nappi02b.gif");
    preload("nappula3", "napit/nappi03.gif", "napit/nappi03b.gif");
    preload("nappula4", "napit/nappi04.gif", "napit/nappi04b.gif");