fn main() {
	let mut s = String::new();
	std::io::stdin().read_line(&mut s).ok();
	let n = s.trim().parse::<usize>().unwrap() - 1;
	let mut d = vec![];
	(1..9).for_each(|a| (a + 1..=9).for_each(|b| d.push(10 * a + b)));
	let a = d[n % d.len()];
	println!("{}{}", a, (a % 10).to_string().repeat(n / d.len()))
}