import java.util.Scanner;
import java.time.LocalDate;

class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        LocalDate ld = LocalDate.of(2015, 01, 01);
        int cnt = 0;
        while (ld.getYear() == 2015) {
            int day = ld.getDayOfMonth();
            int a = day / 10;
            int b = day % 10;
            if (a + b == ld.getMonthValue()) {
                cnt++;
            }
            ld = ld.plusDays(1);
        }
        System.out.println(cnt);
        scan.close();
    }
}