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if ((month == 4) || (month == 6) || (month == 9) || (month == 11)){
         if (day > 30) {
            day -= 30;
            month++;
        }
        else if (day < 1) {
            month--;
            if ((month == 4) || (month == 6) || (month == 9) || (month == 11)){
            day = day + 1;
            }
            else if  (day < 1) {
                day = day - 1;
                month ++;
            }
        } 
    }