#include <stdio.h>

int c[100001];

int main()
{
	int N,M;
	scanf ("%d %d",&N,&M);
	while (M--){
		int x,y; scanf ("%d %d",&x,&y);
		c[x]++; c[y]++;
	}
	for (int i=1;i<=N;i++) if (c[i] % 2){
		puts("NO");
		return 0;
	}
	puts("YES");
	return 0;
}