import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

public class Test {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		Set<Integer> set1 = new HashSet<Integer>();
		Set<Integer> set2 = new HashSet<Integer>();
		int n = sc.nextInt(), tmp, cnt = 0;
		for(int i = 0; i < n; i++){
			tmp = sc.nextInt();
			if(!set1.contains(tmp)){
				set1.add(tmp);
			} else {
				set2.add(tmp);
			}
		}
		System.out.println(set1.size()-set2.size());
	}
}