#include<bits/stdc++.h>
#include<atcoder/all>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef vector<int> vi;
typedef vector<long long> vl;
typedef vector<vector<int>> vvi;
typedef vector<vector<long long>> vvl;
typedef long double ld;
typedef pair<int, int> P;

ostream& operator<<(ostream& os, const modint& a) {os << a.val(); return os;}
template <int m> ostream& operator<<(ostream& os, const static_modint<m>& a) {os << a.val(); return os;}
template <int m> ostream& operator<<(ostream& os, const dynamic_modint<m>& a) {os << a.val(); return os;}
template<typename T> istream& operator>>(istream& is, vector<T>& v){int n = v.size(); assert(n > 0); rep(i, n) is >> v[i]; return is;}
template<typename U, typename T> ostream& operator<<(ostream& os, const pair<U, T>& p){os << p.first << ' ' << p.second; return os;}
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v){int n = v.size(); rep(i, n) os << v[i] << (i == n - 1 ? "\n" : " "); return os;}
template<typename T> ostream& operator<<(ostream& os, const vector<vector<T>>& v){int n = v.size(); rep(i, n) os << v[i] << (i == n - 1 ? "\n" : ""); return os;}

template<typename T> void chmin(T& a, T b){a = min(a, b);}
template<typename T> void chmax(T& a, T b){a = max(a, b);}

// Weighted Union Find 
// O(alpha(N))
// thanks for "https://ei1333.github.io/luzhiled/snippets/structure/union-find.html"
template<typename T>
struct WeightedUnionFind {
	vector<int> data;
	vector<T> ws;
	WeightedUnionFind() {}
	WeightedUnionFind(int sz) : data(sz, -1), ws(sz) {}
	int root(int k){
		if(data[k] < 0) return k;
		auto par = root(data[k]);
		ws[k] += ws[data[k]];
		return data[k] = par;
	}
	T weight(int t) {
		root(t);
		return ws[t];
	}
	bool same(int x, int y){
		x = root(x), y = root(y);
		if(x == y) return true;
		else return false;
	}
	bool unite(int x, int y, T w) {
		w += weight(x);
		w -= weight(y);
		x = root(x), y = root(y);
		if(x == y) return false;
		if(data[x] > data[y]) {
			swap(x, y);
			w *= -1;
		}
		data[x] += data[y];
		data[y] = x;
		ws[y] = w;
		return true;
	}
	T diff(int x, int y) {
		return weight(y) - weight(x);
	}
};

int main(){
	int n, m;
	cin >> n >> m;
	WeightedUnionFind<int> uf(n);
	rep(i, m){
		int u, v;
		cin >> u >> v;
		u--; v--;
		if(uf.same(u, v)){
			int w = uf.diff(u, v);
			if(abs(w) % 2 == 0){
				cout << "No\n";
				return 0;
			}
		}else{
			uf.unite(u, v, 1);
		}
	}
	cout << "Yes\n";
	return 0;
}