#include <bits/stdc++.h>
using namespace std;
int A[100000 + 100];
int N, M;
int main()
{
	scanf("%d%d", &N, &M);
	while (M --)
	{
		int x, y;
		scanf("%d%d", &x, &y);
		A[x] ++, A[y] ++;
	}
	for (int i = 1; i <= N; ++i)
		if (A[i] & 1)
		{
			puts("NO");
			return 0;
		}
	puts("YES");
	return 0;
}