#include <bits/stdc++.h>
#ifdef LOCAL
#include "./debug.cpp"
#else
#define debug(...)
#define print_line
#endif
using namespace std;
using ll = long long;

int main() {
    int N, M;
    cin >> N >> M;
    vector<vector<int>> G(N);
    for (int i = 0; i < M; i++) {
        int a, b;
        cin >> a >> b;
        a--;
        b--;
        G[a].push_back(b);
        G[b].push_back(a);
    }

    vector<int> C(N, -1);
    bool ans = true;
    for (int i = 0; i < N; i++) {
        if (C[i] == -1) {
            C[i] = 0;
            queue<int> Q;
            Q.push(i);
            while (!Q.empty()) {
                int now = Q.front();
                Q.pop();
                for (int nxt : G[now]) {
                    if (C[nxt] == -1) {
                        C[nxt] = 1 - C[now];
                        Q.push(nxt);
                    }
                    if (C[nxt] == C[now]) {
                        ans = false;
                    }
                }
            }
        }
    }

    puts(ans ? "Yes" : "No");
}