import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        B solver = new B();
        solver.solve(1, in, out);
        out.close();
    }

    static class B {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            byte N = Byte.parseByte(in.next());
            Set<Byte> d = new HashSet<>();
            for (byte i = 0; i < N; i++) {
                d.add(Byte.parseByte(in.next()));
            }
            out.println(d.size());
        }

    }
}
 import java.io.OutputStream; OutputStream java.io import java.io.IOException; IOException java.io import java.io.InputStream; InputStream java.io import java.io.PrintWriter; PrintWriter java.io import java.util.HashSet; HashSet java.util import java.util.Scanner; Scanner java.util import java.util.Set; Set java.util public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        B solver = new B();
        solver.solve(1, in, out);
        out.close();
    }

    static class B {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            byte N = Byte.parseByte(in.next());
            Set<Byte> d = new HashSet<>();
            for (byte i = 0; i < N; i++) {
                d.add(Byte.parseByte(in.next()));
            }
            out.println(d.size());
        }

    }
} Main public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        B solver = new B();
        solver.solve(1, in, out);
        out.close();
    } main {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        B solver = new B();
        solver.solve(1, in, out);
        out.close();
    } InputStream inputStream = System.in; inputStream System.in System System.in OutputStream outputStream = System.out; outputStream System.out System System.out Scanner in = new Scanner(inputStream); in new Scanner(inputStream) PrintWriter out = new PrintWriter(outputStream); out new PrintWriter(outputStream) B solver = new B(); solver new B() solver.solve(1, in, out) solver.solve solver 1 in out out.close() out.close out String[] args args static class B {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            byte N = Byte.parseByte(in.next());
            Set<Byte> d = new HashSet<>();
            for (byte i = 0; i < N; i++) {
                d.add(Byte.parseByte(in.next()));
            }
            out.println(d.size());
        }

    } B public void solve(int testNumber, Scanner in, PrintWriter out) {
            byte N = Byte.parseByte(in.next());
            Set<Byte> d = new HashSet<>();
            for (byte i = 0; i < N; i++) {
                d.add(Byte.parseByte(in.next()));
            }
            out.println(d.size());
        } solve {
            byte N = Byte.parseByte(in.next());
            Set<Byte> d = new HashSet<>();
            for (byte i = 0; i < N; i++) {
                d.add(Byte.parseByte(in.next()));
            }
            out.println(d.size());
        } byte N = Byte.parseByte(in.next()); N Byte.parseByte(in.next()) Byte.parseByte Byte in.next() in.next in Set<Byte> d = new HashSet<>(); d new HashSet<>() for (byte i = 0; i < N; i++) {
                d.add(Byte.parseByte(in.next()));
            } byte i = 0; byte i = 0; i 0 i < N i N i++ i++ i {
                d.add(Byte.parseByte(in.next()));
            } {
                d.add(Byte.parseByte(in.next()));
            } d.add(Byte.parseByte(in.next())) d.add d Byte.parseByte(in.next()) Byte.parseByte Byte in.next() in.next in out.println(d.size()) out.println out d.size() d.size d int testNumber testNumber Scanner in in PrintWriter out out public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        B solver = new B();
        solver.solve(1, in, out);
        out.close();
    }

    static class B {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            byte N = Byte.parseByte(in.next());
            Set<Byte> d = new HashSet<>();
            for (byte i = 0; i < N; i++) {
                d.add(Byte.parseByte(in.next()));
            }
            out.println(d.size());
        }

    }
} public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        B solver = new B();
        solver.solve(1, in, out);
        out.close();
    }

    static class B {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            byte N = Byte.parseByte(in.next());
            Set<Byte> d = new HashSet<>();
            for (byte i = 0; i < N; i++) {
                d.add(Byte.parseByte(in.next()));
            }
            out.println(d.size());
        }

    }
} Main
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        B solver = new B();
        solver.solve(1, in, out);
        out.close();
    }

    static class B {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            byte N = Byte.parseByte(in.next());
            Set<Byte> d = new HashSet<>();
            for (byte i = 0; i < N; i++) {
                d.add(Byte.parseByte(in.next()));
            }
            out.println(d.size());
        }

    }
}

