import java.util.*;
class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		
		int[] list = new int[n];
		for(int i = 0; i < n; i++) {
			list[i] = sc.nextInt();
		}
		
		Arrays.sort(list);
		int count = 0;
		for(int i = 0; i < n-1; i++) {
			if(list[i] != list[i+1] ){
				count++;
				if(i == n-2) {
				count++;
				}
			}
			else {
				for(int j = i+1; j < n; j++) {
					if(list[i] != list[j]) {
						i = j-1;
						if(i == n-1) {
							count++;
						}
						break;
					}
				}
			}
		}
		
		System.out.println(count);
		
		
		
				
	}
}