import java.util.*;
import java.util.stream.IntStream;
class M{
	static Scanner s=new Scanner(System.in);
	static int getInt(){return Integer.parseInt(s.next());}
	static IntStream REPS(int v){return IntStream.range(0,v);}
	static IntStream INS(int n) {return REPS(n).map(i->getInt());}
	public static void main(String[]$){
		HashMap<Integer,Integer>hm=new HashMap<>();
		INS(getInt()).forEach(i->hm.merge(i,1,Integer::sum));
		System.out.println(
				hm.values().stream()
				.filter(i->i==1)
				.count()
				);
	}
}