fn main() {
    let mut ans = 0;
    for m in 1..=12 {
        let d = match m {
            1 | 3 | 5 | 7 | 8 | 10 | 12 => 31,
            4 | 6 | 9 | 11 => 30,
            2 => 28,
            _ => unreachable!(),
        };
        for d in 1..=d {
            if d % 10 + d / 10 == m {
                ans += 1;
            }
        }
    }
    println!("{}", ans);
}