#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } else { return false; } }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } else { return false; } }
#define rep(i, s, n) for(int i = (s); i < n; i++) 
#define reps(i, s, n) for(int i = (s); i <= n; i++) 
#define rrep(i, n, s) for(int i = n; i >= (s); i--)
#define all(x) (x).begin(), (x).end()
#define print(V) for (int z = 0; z < (V).size(); z++) { cout << V[z] << " "; } cout << endl;
#define MOD 998244353
#define MOD2 1000000007
#define INF 1LL << 60
#define PI acos(-1)

struct UnionFind {
	vector<int> par;

	UnionFind(int n) : par(n, -1) { }
	void init(int n) { par.assign(n, -1); }

	int root(int x) {
		if (par[x] < 0) return x;
		else return par[x] = root(par[x]);
	}

	bool issame(int x, int y) {
		return root(x) == root(y);
	}

	bool merge(int x, int y) {
		x = root(x); y = root(y);
		if (x == y) return false;
		if (par[x] > par[y]) swap(x, y);
		par[x] += par[y];
		par[y] = x;
		return true;
	}

	int size(int x) {
		return -par[root(x)];
	}
};

int main(void) {
	int n, m;
	cin >> n >> m;

	UnionFind uf(2 * n);
	int a, b;
	rep(i, 0, m) {
		cin >> a >> b;
		a--;
		b--;
		uf.merge(a, b + n);
		uf.merge(a + n, b);
	}

	bool flag = true;
	rep(i, 0, n) {
		if (!uf.issame(i, i + n)) {
			flag = false;
		}
	}

	if (flag) {
		cout << "Yes" << endl;
	}
	else {
		cout << "No" << endl;
	}

	return 0;
}