import java.util.Arrays;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		final int n = sc.nextInt(), d[] = new int[n + 1];
		for(int i = 0; i < n; ++i) 
			d[i] = sc.nextInt();
		sc.close();
		d[n] = 1000;
		Arrays.sort(d);
		int ans = 0;
		for(int i = 0; i < n; ++i) {
			if(d[i] != d[i + 1])++ans;
		}
		System.out.println(ans);
	}

} import java.util.Arrays; Arrays java.util import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		final int n = sc.nextInt(), d[] = new int[n + 1];
		for(int i = 0; i < n; ++i) 
			d[i] = sc.nextInt();
		sc.close();
		d[n] = 1000;
		Arrays.sort(d);
		int ans = 0;
		for(int i = 0; i < n; ++i) {
			if(d[i] != d[i + 1])++ans;
		}
		System.out.println(ans);
	}

} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		final int n = sc.nextInt(), d[] = new int[n + 1];
		for(int i = 0; i < n; ++i) 
			d[i] = sc.nextInt();
		sc.close();
		d[n] = 1000;
		Arrays.sort(d);
		int ans = 0;
		for(int i = 0; i < n; ++i) {
			if(d[i] != d[i + 1])++ans;
		}
		System.out.println(ans);
	} main {
		Scanner sc = new Scanner(System.in);
		final int n = sc.nextInt(), d[] = new int[n + 1];
		for(int i = 0; i < n; ++i) 
			d[i] = sc.nextInt();
		sc.close();
		d[n] = 1000;
		Arrays.sort(d);
		int ans = 0;
		for(int i = 0; i < n; ++i) {
			if(d[i] != d[i + 1])++ans;
		}
		System.out.println(ans);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) final int n = sc.nextInt() n sc.nextInt() sc.nextInt sc d[] = new int[n + 1]; d new int[n + 1] n + 1 n 1 for(int i = 0; i < n; ++i) 
			d[i] = sc.nextInt(); int i = 0; int i = 0; i 0 i < n i n ++i ++i i d[i] = sc.nextInt(); d[i] = sc.nextInt() d[i] d i sc.nextInt() sc.nextInt sc sc.close() sc.close sc d[n] = 1000 d[n] d n 1000 Arrays.sort(d) Arrays.sort Arrays d int ans = 0; ans 0 for(int i = 0; i < n; ++i) {
			if(d[i] != d[i + 1])++ans;
		} int i = 0; int i = 0; i 0 i < n i n ++i ++i i {
			if(d[i] != d[i + 1])++ans;
		} {
			if(d[i] != d[i + 1])++ans;
		} if(d[i] != d[i + 1])++ans; d[i] != d[i + 1] d[i] d i d[i + 1] d i + 1 i 1 ++ans ans System.out.println(ans) System.out.println System.out System System.out ans String[] args args public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		final int n = sc.nextInt(), d[] = new int[n + 1];
		for(int i = 0; i < n; ++i) 
			d[i] = sc.nextInt();
		sc.close();
		d[n] = 1000;
		Arrays.sort(d);
		int ans = 0;
		for(int i = 0; i < n; ++i) {
			if(d[i] != d[i + 1])++ans;
		}
		System.out.println(ans);
	}

} public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		final int n = sc.nextInt(), d[] = new int[n + 1];
		for(int i = 0; i < n; ++i) 
			d[i] = sc.nextInt();
		sc.close();
		d[n] = 1000;
		Arrays.sort(d);
		int ans = 0;
		for(int i = 0; i < n; ++i) {
			if(d[i] != d[i + 1])++ans;
		}
		System.out.println(ans);
	}

} Main
import java.util.Arrays;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		final int n = sc.nextInt(), d[] = new int[n + 1];
		for(int i = 0; i < n; ++i) 
			d[i] = sc.nextInt();
		sc.close();
		d[n] = 1000;
		Arrays.sort(d);
		int ans = 0;
		for(int i = 0; i < n; ++i) {
			if(d[i] != d[i + 1])++ans;
		}
		System.out.println(ans);
	}

}
