#include <bits/stdc++.h>
using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int N,M; cin >> N >> M;
    vector<vector<int>> Graph(N);
    for(int i=0; i<M; i++){
        int u,v; cin >> u >> v;
        u--; v--;
        Graph.at(u).push_back(v);
        Graph.at(v).push_back(u);
    }    

    vector<int> dist(N,-1);
    vector<bool> already(N);
    bool yes = true;
    for(int i=0; i<N; i++){
        if(already.at(i)) continue;
        dist.at(i) = 0;
        queue<int> Q; Q.push(i);
        while(Q.size()){
            int pos = Q.front(); Q.pop();
            already.at(pos) = true;
            int nd = dist.at(pos)^1;
            for(auto to : Graph.at(pos)){
                if(dist.at(to) == -1){
                    dist.at(to) = nd;
                    Q.push(to);
                }
                else if(dist.at(to) != nd) yes = false;
            }
        }
    }
    if(yes) cout << "Yes" << endl;
    else cout << "No" << endl;
}