import java.util.*;
import java.io.*;

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

        int d[] = new int[n];
        for(int i = 0; i < n; i++){
            d[i] = Integer.parseInt(sc.next());
        }

        int num[] = new int [101];
        for(int i = 0; i < n; i++){
            num[d[i]]++;
        }

        int cnt = 0;
        for (int i = 0; i < 101; i++) {
            if(num[i] > 0){
                cnt++;
            }
        }

        System.out.println(cnt);
    }
} import java.util.*; util.* java import java.io.*; io.* java public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.parseInt(sc.next());

        int d[] = new int[n];
        for(int i = 0; i < n; i++){
            d[i] = Integer.parseInt(sc.next());
        }

        int num[] = new int [101];
        for(int i = 0; i < n; i++){
            num[d[i]]++;
        }

        int cnt = 0;
        for (int i = 0; i < 101; i++) {
            if(num[i] > 0){
                cnt++;
            }
        }

        System.out.println(cnt);
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.parseInt(sc.next());

        int d[] = new int[n];
        for(int i = 0; i < n; i++){
            d[i] = Integer.parseInt(sc.next());
        }

        int num[] = new int [101];
        for(int i = 0; i < n; i++){
            num[d[i]]++;
        }

        int cnt = 0;
        for (int i = 0; i < 101; i++) {
            if(num[i] > 0){
                cnt++;
            }
        }

        System.out.println(cnt);
    } main {
        Scanner sc = new Scanner(System.in);
        int n = Integer.parseInt(sc.next());

        int d[] = new int[n];
        for(int i = 0; i < n; i++){
            d[i] = Integer.parseInt(sc.next());
        }

        int num[] = new int [101];
        for(int i = 0; i < n; i++){
            num[d[i]]++;
        }

        int cnt = 0;
        for (int i = 0; i < 101; i++) {
            if(num[i] > 0){
                cnt++;
            }
        }

        System.out.println(cnt);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = Integer.parseInt(sc.next()); n Integer.parseInt(sc.next()) Integer.parseInt Integer sc.next() sc.next sc int d[] = new int[n]; d new int[n] n for(int i = 0; i < n; i++){
            d[i] = Integer.parseInt(sc.next());
        } int i = 0; int i = 0; i 0 i < n i n i++ i++ i {
            d[i] = Integer.parseInt(sc.next());
        } {
            d[i] = Integer.parseInt(sc.next());
        } d[i] = Integer.parseInt(sc.next()) d[i] d i Integer.parseInt(sc.next()) Integer.parseInt Integer sc.next() sc.next sc int num[] = new int [101]; num new int [101] 101 for(int i = 0; i < n; i++){
            num[d[i]]++;
        } int i = 0; int i = 0; i 0 i < n i n i++ i++ i {
            num[d[i]]++;
        } {
            num[d[i]]++;
        } num[d[i]]++ num[d[i]] num d[i] d i int cnt = 0; cnt 0 for (int i = 0; i < 101; i++) {
            if(num[i] > 0){
                cnt++;
            }
        } int i = 0; int i = 0; i 0 i < 101 i 101 i++ i++ i {
            if(num[i] > 0){
                cnt++;
            }
        } {
            if(num[i] > 0){
                cnt++;
            }
        } if(num[i] > 0){
                cnt++;
            } num[i] > 0 num[i] num i 0 {
                cnt++;
            } cnt++ cnt System.out.println(cnt) System.out.println System.out System System.out cnt String[] args args public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.parseInt(sc.next());

        int d[] = new int[n];
        for(int i = 0; i < n; i++){
            d[i] = Integer.parseInt(sc.next());
        }

        int num[] = new int [101];
        for(int i = 0; i < n; i++){
            num[d[i]]++;
        }

        int cnt = 0;
        for (int i = 0; i < 101; i++) {
            if(num[i] > 0){
                cnt++;
            }
        }

        System.out.println(cnt);
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = Integer.parseInt(sc.next());

        int d[] = new int[n];
        for(int i = 0; i < n; i++){
            d[i] = Integer.parseInt(sc.next());
        }

        int num[] = new int [101];
        for(int i = 0; i < n; i++){
            num[d[i]]++;
        }

        int cnt = 0;
        for (int i = 0; i < 101; i++) {
            if(num[i] > 0){
                cnt++;
            }
        }

        System.out.println(cnt);
    }
} Main
import java.util.*;
import java.io.*;

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

        int d[] = new int[n];
        for(int i = 0; i < n; i++){
            d[i] = Integer.parseInt(sc.next());
        }

        int num[] = new int [101];
        for(int i = 0; i < n; i++){
            num[d[i]]++;
        }

        int cnt = 0;
        for (int i = 0; i < 101; i++) {
            if(num[i] > 0){
                cnt++;
            }
        }

        System.out.println(cnt);
    }
}