use std::io;
fn main() {
    let v = input_nums();
    let (x, a, y, b) = (v[0], v[1], v[2], v[3]);

    println!(
        "{}",
        if (a * x.log10() / (b * y.log10())).abs() >= 1.0 {
            "Yes"
        } else {
            "No"
        }
    );
}

fn input_nums() -> Vec<f64> {
    let mut s = String::new();
    io::stdin().read_line(&mut s).unwrap();
    let mut v = Vec::new();
    for n in s.split_whitespace() {
        v.push(n.parse().unwrap());
    }
    v
}