import java.util.ArrayList;
import java.util.HashSet;
import java.util.Scanner;


public class Main {
	static int N;
	static ArrayList<Integer> A;
			
	static private void solve()
	{
		int ans = 0;
		int prenum = -1;
		int count = 0;
		for (Integer i : A) {
			if(i == prenum) 
				{
				count++;
				}
			else {
				prenum = i;
				if(count == 1) ans++;
				count = 1;
			}
		}
		if (count == 1) ans++;
		
		System.out.println(ans);
	}
	
	static public void main(String[] args)
	{
		Scanner sca = new Scanner(System.in);
		
		N = sca.nextInt();
		
		A = new ArrayList<Integer>();
		for (int i = 0; i < N; i++) {
			A.add(new Integer(sca.nextInt()));
		}
		
		A.sort(null);
		
		solve();
	}
}