fn main() {
    let n = read::<usize>();
    let ans = (1..n + 1)
        .map(|x| n / x)
        .collect::<std::collections::HashSet<_>>()
        .len();
    println!("{}", ans);
}

fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}