use ac_library::Dsu;
use proconio::{input, marker::Usize1};

fn main() {
    input! {
        n: usize, m: usize,
        edges: [(Usize1, Usize1); m],
    }

    let mut dsu = Dsu::new(n);
    let mut graph = vec![vec![]; n];
    for &(u, v) in &edges {
        if !dsu.same(u, v) {
            dsu.merge(u, v);
            graph[u].push(v);
            graph[v].push(u);
        }
    }

    let mut color = vec![false; n];
    let mut stack = vec![];

    for root in 0..n {
        stack.push((root, !0));

        while let Some((v, p)) = stack.pop() {
            for &u in &graph[v] {
                if u == p {
                    continue;
                }
                color[u] = !color[v];
                stack.push((u, v));
            }
        }
    }

    let ans = edges.iter().all(|&(u, v)| color[u] != color[v]);
    println!("{}", if ans { "Yes" } else { "No" });
}