import java.util.*;

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

		int N = sc.nextInt(), min = Integer.MAX_VALUE, max = Integer.MIN_VALUE, cnt = 0;
		int[] a = new int[N];
		
		for(int i = 0; i < N; i++) {
			a[i] = sc.nextInt();
			
			min = Math.min(min, a[i]);
			max = Math.max(max, a[i]);
		}
		
		int[] A = new int[max - min + 1];
	
		for(int i = 0; i < N; i++) {
			A[a[i] - 1]++;
		}
		
		for(int i = 0; i < A.length; i++) {
			if(A[i] == 1)	cnt++;
		}
		
		System.out.println(cnt);
	}
}