import java.util.Scanner;
 
class Main {
	int n;
	int[] d;
	
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		Main m = new Main(sc);
		m.solve();
		sc.close();
	}
	Main(Scanner sc){
		n = sc.nextInt();
		d = new int[n];
		for(int i=0;i<n;i++){
			d[i] = sc.nextInt();
		}
	}
	void solve(){
		boolean[] cnt = new boolean[100];
		for(int i=0;i<n;i++){
			cnt[d[i]-1] = true;
		}
		int dan = 0;
		for(boolean f : cnt){
			if(f) dan++;
		}
		System.out.println(dan);
	}
} import java.util.Scanner; Scanner java.util class Main {
	int n;
	int[] d;
	
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		Main m = new Main(sc);
		m.solve();
		sc.close();
	}
	Main(Scanner sc){
		n = sc.nextInt();
		d = new int[n];
		for(int i=0;i<n;i++){
			d[i] = sc.nextInt();
		}
	}
	void solve(){
		boolean[] cnt = new boolean[100];
		for(int i=0;i<n;i++){
			cnt[d[i]-1] = true;
		}
		int dan = 0;
		for(boolean f : cnt){
			if(f) dan++;
		}
		System.out.println(dan);
	}
} Main int n; n int[] d; d public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		Main m = new Main(sc);
		m.solve();
		sc.close();
	} main {
		Scanner sc = new Scanner(System.in);
		Main m = new Main(sc);
		m.solve();
		sc.close();
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) Main m = new Main(sc); m new Main(sc) m.solve() m.solve m sc.close() sc.close sc String[] args args Main(Scanner sc){
		n = sc.nextInt();
		d = new int[n];
		for(int i=0;i<n;i++){
			d[i] = sc.nextInt();
		}
	} Main {
		n = sc.nextInt();
		d = new int[n];
		for(int i=0;i<n;i++){
			d[i] = sc.nextInt();
		}
	} n = sc.nextInt() n sc.nextInt() sc.nextInt sc d = new int[n] d new int[n] n 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] = sc.nextInt() d[i] d i sc.nextInt() sc.nextInt sc Scanner sc sc void solve(){
		boolean[] cnt = new boolean[100];
		for(int i=0;i<n;i++){
			cnt[d[i]-1] = true;
		}
		int dan = 0;
		for(boolean f : cnt){
			if(f) dan++;
		}
		System.out.println(dan);
	} solve {
		boolean[] cnt = new boolean[100];
		for(int i=0;i<n;i++){
			cnt[d[i]-1] = true;
		}
		int dan = 0;
		for(boolean f : cnt){
			if(f) dan++;
		}
		System.out.println(dan);
	} boolean[] cnt = new boolean[100]; cnt new boolean[100] 100 for(int i=0;i<n;i++){
			cnt[d[i]-1] = true;
		} int i=0; int i=0; i 0 i<n i n i++ i++ i {
			cnt[d[i]-1] = true;
		} {
			cnt[d[i]-1] = true;
		} cnt[d[i]-1] = true cnt[d[i]-1] cnt d[i]-1 d[i] d i 1 true int dan = 0; dan 0 for(boolean f : cnt){
			if(f) dan++;
		} boolean f cnt {
			if(f) dan++;
		} {
			if(f) dan++;
		} if(f) dan++; f dan++ dan System.out.println(dan) System.out.println System.out System System.out dan
import java.util.Scanner;
 
class Main {
	int n;
	int[] d;
	
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		Main m = new Main(sc);
		m.solve();
		sc.close();
	}
	Main(Scanner sc){
		n = sc.nextInt();
		d = new int[n];
		for(int i=0;i<n;i++){
			d[i] = sc.nextInt();
		}
	}
	void solve(){
		boolean[] cnt = new boolean[100];
		for(int i=0;i<n;i++){
			cnt[d[i]-1] = true;
		}
		int dan = 0;
		for(boolean f : cnt){
			if(f) dan++;
		}
		System.out.println(dan);
	}
}