import java.util.GregorianCalendar;

public class Main {
    public static void main(String[] args) throws Exception {
        // Scanner sc = new Scanner(System.in);
        //int a = sc.nextInt();
        //int b = sc.nextInt();
        GregorianCalendar calendar = new GregorianCalendar(2015, 0, 31);
        GregorianCalendar endDay = new GregorianCalendar(2015, 11, 31);
        int count = 0;
        int d10 = 0;
        int d1 = 0;
        
        for (int i = 1; i <= 365; i++ ) {
            int m = calendar.get(calendar.MONTH);
            int d = calendar.get(calendar.DATE);
            if (d > 9) {
                d10 = d/10;
                d1 = d%10;
            } else {
                d1 = d;
            }
            
            if (m == d10 + d1) {
                count++;
            }
            calendar.add(calendar.DATE, 1);
        }
        System.out.println(count);
    }
}