#include <bits/stdc++.h>
#define N 1000500
using namespace std;

inline int rd() {int r;scanf("%d",&r);return r;}
int n,m,d[N];
int main() {
    n = rd(), m = rd();
    for (int i=1;i<=m;i++) d[rd()]++, d[rd()]++;
    int ans = 1;
    for (int i=1;i<=n;i++) if (d[i]&1) ans = 0;
    puts(ans?"YES":"NO");
    return 0;
}