w = self;
function weekNo() {
  var totalDays = 0;  		
  now = new Date();
  years=now.getYear()
  if (years < 1000)
  years+=1900
  var days = new Array(12);
  days[0] = 31;
  days[2] = 31;
  days[3] = 30;
  days[4] = 31;
  days[5] = 30;
  days[6] = 31;
  days[7] = 31;
  days[8] = 30;
  days[9] = 31;
  days[10] = 30;
  days[11] = 31;

   if (Math.round(now.getYear()/4) == now.getYear()/4) {
     days[1] = 29
  }else{
     days[1] = 28
  }

  if (now.getMonth() == 0) {		
     totalDays = totalDays + now.getDate();
  }else{
     var curMonth = now.getMonth();
     for (var count = 1; count <= curMonth; count++) {
         totalDays = totalDays + days[count - 1];
     }
     totalDays = totalDays + now.getDate();
   }
   var week = Math.round(totalDays/7);
   return week;
}
document.write(+weekNo()+"<sup>e</sup> semaine")
