use std::io::Read;

fn solve(d: usize) {
    println!("{}", (1..60).map(|i| i.to_string()).collect::<Vec<String>>().join("").chars().skip(d-1).next().unwrap());
}

fn main() {
    let mut d = String::new();
    std::io::stdin().read_to_string(&mut d).ok();
    let d: usize = d.trim().split('\n').next().unwrap().trim().parse::<usize>().unwrap();
    solve(d);
}