function nightChange(v) {
 //var d = document.forms['ricerca'];
 //var n = d.notti.value;
 var n = document.forms['ricerca'].notti.value;
 var date = new Date(c_1.getValue());
 date.setDate(Number(date.getDate()) + Number(n));
 c_2.setValue2(date);
}
function EndDateChange() {
 var d = document.forms['ricerca'];
 var n = d.notti.value;
  datDate1= Date.parse(c_1.getValue()); 
  datDate2= Date.parse(c_2.getValue()); 
  datediff = ((datDate2-datDate1)/(24*60*60*1000)) 
  d.notti.value=datediff;
}