static int getIndex(int year,int month ,int day){
        Calendar calendar=new GregorianCalendar(TimeZone.getTimeZone("GMT"));
        calendar.set(Calendar.YEAR,year);
        calendar.set(Calendar.MONTH,month-1);
        calendar.set(Calendar.DATE,day);
        calendar.set(Calendar.HOUR_OF_DAY,0);
        calendar.set(Calendar.MINUTE,0);
        calendar.set(Calendar.SECOND,0);
        calendar.set(Calendar.MILLISECOND,0);

        return (int)((calendar.getTime().getTime()-startDay.getTime())/milliSecondsOnyDay);
    }