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

const int N = 1e5 + 100;

int n, m, u, v, cnt[N];

int main() {
	ios::sync_with_stdio(false), cin.tie(0);
	cin >> n >> m;
	while(m--) {
		cin >> u >> v;
		cnt[--u]++;
		cnt[--v]++;
	}
	for (int i = 0; i < n; i++)
		if(cnt[i] & 1) {
			cout << "NO";
			return 0;
		}
	cout << "YES";
	return 0;
}