fn main() {
    let mut xx = String::new();
    std::io::stdin().read_line(&mut xx).ok();
    let mut xx: Vec<u64> = xx.split_whitespace().flat_map(str::parse).collect();

    xx.sort_unstable();
    xx.dedup();

    if xx.len() == 4 && xx[3] == xx[0] + 3 {
        println!("Yes");
    } else {
        println!("No");
    }
}