#include<cstdio>
int n,a[100001],b[100001],m,d[100001];
bool ok;
int main()
{
	scanf("%d%d",&n,&m);
	for(int i=1;i<=m;++i)scanf("%d%d",a+i,b+i),d[a[i]]++,d[b[i]]++;
	for(int i=1;i<=n;++i)if(d[i]&1){puts("NO");return 0;}
	puts("YES");
	return 0;
}