fn main() {
	let mut s = String::new();
	std::io::stdin().read_line(&mut s).ok();

    let ans = if s.chars()
        .enumerate()
        .all(|(i, c)| {
            (i % 2 == 0) == (c != ' ')
        }) {
            "Yes"
        } else {
            "No"
        };

	println!("{ans}");
}