fn main() {
    let n = {
        let mut line = String::new();
        std::io::stdin().read_line(&mut line).unwrap();
        line.trim().parse::<usize>().unwrap()
    };

    let (digit_num, rem) = ((n - 1) / 36 + 2, (n - 1) % 36);
    let (a, b) = {
        let mut rem = rem;

        let a = (1..=8)
            .find(|&i| {
                if 9 - i > rem {
                    return true;
                }

                rem -= 9 - i;

                false
            })
            .unwrap();

        (a, a + 1 + rem)
    };

    println!("{}{}", a, b.to_string().repeat(digit_num - 1));
}