fn main() {
    let mut d = String::new();
    std::io::stdin().read_line(&mut d).ok();
    let d: usize = d.trim().parse().unwrap();

    let c10: Vec<char> = (1..100)
        .flat_map(|n| n.to_string().chars().collect::<Vec<_>>())
        .collect();

    println!("{}", c10[d - 1]);
}