#[allow(unused_imports)]
use proconio::{
    input,
    marker::{Bytes, Chars, Usize1},
};
fn main() {
    input!(n: Chars);
    let a = n[0].to_digit(10).unwrap();
    let b = n[1].to_digit(10).unwrap();
    let c = n[2].to_digit(10).unwrap();
    let res = if a + c == b { "Yes" } else { "No" };
    println!("{}", res);
}