using namespace std;
int main(){
	int a;
	cin>>a;
	if(a%2==0 || a>50){
  		cout<<"yes";
  	}
  	else{
  		cout<<"no";
  	}
  return 0;
}

using namespace std;
int main()
{
  int a,b,c;
  cin>>a;
  if(a%2==0 or a>50){
  	cout<<"yes"<<endl;
  }else{
  	cout<<"no"<<endl;
  }
  return 0;
}