#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> C(N,-1);
    queue<int> Q;
    for(int i=0; i<N; i++) if(C.at(i) == -1){
        Q.push(i),C.at(i) = 0;
        while(Q.size()){
            int pos = Q.front(); Q.pop();
            for(auto to : Graph.at(pos)){
                if(C.at(to) == -1) C.at(to) = C.at(pos)^1,Q.push(to);
                else if(C.at(to) == C.at(pos)){cout << "No\n"; return 0;}
            }
        }
    }
    cout << "Yes\n";
}