import java.util.*;
public class No188 {
	public static void main(String[] args) {
		int day_Goukei,HappyDay=0;
		String moji_day;
		GregorianCalendar GC =new GregorianCalendar(2015,0,1);
		for(int month=1;month<=GC.getMaximum(GregorianCalendar.MONTH)+1;month++){
			for(int day=1; day<=GC.getActualMaximum(GregorianCalendar.DAY_OF_MONTH);day++){
				if(day>=10){
					moji_day =Integer.toString(day);
					day_Goukei=Integer.parseInt(moji_day.substring(0,1))+Integer.parseInt(moji_day.substring(1,2));
				}else{
					day_Goukei=day;
				}
				if(month==day_Goukei){
					HappyDay++;					
				}
			}
			GC.set(GregorianCalendar.MONTH, month);
		}
		System.out.println(HappyDay);
	}
}