public String getNext(String date, String[] birthdays) {
		birthday[] bi = new birthday[birthdays.length];
		for(int i = 0;i < birthdays.length;i++){
			bi[i] = new birthday(Integer.parseInt(birthdays[i].substring(0,2)), Integer.parseInt(birthdays[i].substring(3,5)),birthdays[i].substring(6));
		}
		Arrays.sort(bi, new birthdayComparator());
		birthday target = new birthday(Integer.parseInt(date.substring(0,2)),Integer.parseInt(date.substring(3,5)),"");
		int position = Arrays.binarySearch(bi, target,new birthdayComparator());
		if(position > 0)
			return date;
		else {
			return -position-1 == birthdays.length?birthdays[0].substring(0,5):birthdays[-position-1].substring(0,5);
		}
	}