import java.util.*;

class Reader {
  Scanner sc = new Scanner(System.in);

  public int ini() {
    return sc.nextInt();
  }

  public int[] vi(int n) {
    int[] a = new int[n];
    for (int i = 0; i < n; i++) a[i] = sc.nextInt();
    return a;
  }
}

public class Main extends Reader {
  public static void main(String[] args) {
    Main main = new Main();
    main.show(main.solve());
  }

  int n;
  int[] a;

  public Main() {
    n = ini();
    a = vi(n);
  }
  
  int solve() {
    int[] cnt = new int[101];
    for (int i = 0; i < n; i++) {
      cnt[a[i]]++;
    }
    int ans = 0;
    for (int i = 1; i <= 100; i++) {
      if (cnt[i] != 0) ans++;
    }
    return ans;
  }

  int calc(int left, int right) {
    int ans = 0;
    for (int i = left; i <= right; i++) {
      ans += i;
    }
    return ans;
  }

  void show(int ans) {
    System.out.println(ans);
  }
}

 import java.util.*; util.* java class Reader {
  Scanner sc = new Scanner(System.in);

  public int ini() {
    return sc.nextInt();
  }

  public int[] vi(int n) {
    int[] a = new int[n];
    for (int i = 0; i < n; i++) a[i] = sc.nextInt();
    return a;
  }
} Reader Scanner sc = new Scanner(System.in); sc new Scanner(System.in) public int ini() {
    return sc.nextInt();
  } ini {
    return sc.nextInt();
  } return sc.nextInt(); sc.nextInt() sc.nextInt sc public int[] vi(int n) {
    int[] a = new int[n];
    for (int i = 0; i < n; i++) a[i] = sc.nextInt();
    return a;
  } vi {
    int[] a = new int[n];
    for (int i = 0; i < n; i++) a[i] = sc.nextInt();
    return a;
  } int[] a = new int[n]; a new int[n] n for (int i = 0; i < n; i++) a[i] = sc.nextInt(); int i = 0; int i = 0; i 0 i < n i n i++ i++ i a[i] = sc.nextInt(); a[i] = sc.nextInt() a[i] a i sc.nextInt() sc.nextInt sc return a; a int n n public class Main extends Reader {
  public static void main(String[] args) {
    Main main = new Main();
    main.show(main.solve());
  }

  int n;
  int[] a;

  public Main() {
    n = ini();
    a = vi(n);
  }
  
  int solve() {
    int[] cnt = new int[101];
    for (int i = 0; i < n; i++) {
      cnt[a[i]]++;
    }
    int ans = 0;
    for (int i = 1; i <= 100; i++) {
      if (cnt[i] != 0) ans++;
    }
    return ans;
  }

  int calc(int left, int right) {
    int ans = 0;
    for (int i = left; i <= right; i++) {
      ans += i;
    }
    return ans;
  }

  void show(int ans) {
    System.out.println(ans);
  }
} Main int n; n int[] a; a public static void main(String[] args) {
    Main main = new Main();
    main.show(main.solve());
  } main {
    Main main = new Main();
    main.show(main.solve());
  } Main main = new Main(); main new Main() main.show(main.solve()) main.show main main.solve() main.solve main String[] args args public Main() {
    n = ini();
    a = vi(n);
  } Main {
    n = ini();
    a = vi(n);
  } n = ini() n ini() ini a = vi(n) a vi(n) vi n int solve() {
    int[] cnt = new int[101];
    for (int i = 0; i < n; i++) {
      cnt[a[i]]++;
    }
    int ans = 0;
    for (int i = 1; i <= 100; i++) {
      if (cnt[i] != 0) ans++;
    }
    return ans;
  } solve {
    int[] cnt = new int[101];
    for (int i = 0; i < n; i++) {
      cnt[a[i]]++;
    }
    int ans = 0;
    for (int i = 1; i <= 100; i++) {
      if (cnt[i] != 0) ans++;
    }
    return ans;
  } int[] cnt = new int[101]; cnt new int[101] 101 for (int i = 0; i < n; i++) {
      cnt[a[i]]++;
    } int i = 0; int i = 0; i 0 i < n i n i++ i++ i {
      cnt[a[i]]++;
    } {
      cnt[a[i]]++;
    } cnt[a[i]]++ cnt[a[i]] cnt a[i] a i int ans = 0; ans 0 for (int i = 1; i <= 100; i++) {
      if (cnt[i] != 0) ans++;
    } int i = 1; int i = 1; i 1 i <= 100 i 100 i++ i++ i {
      if (cnt[i] != 0) ans++;
    } {
      if (cnt[i] != 0) ans++;
    } if (cnt[i] != 0) ans++; cnt[i] != 0 cnt[i] cnt i 0 ans++ ans return ans; ans int calc(int left, int right) {
    int ans = 0;
    for (int i = left; i <= right; i++) {
      ans += i;
    }
    return ans;
  } calc {
    int ans = 0;
    for (int i = left; i <= right; i++) {
      ans += i;
    }
    return ans;
  } int ans = 0; ans 0 for (int i = left; i <= right; i++) {
      ans += i;
    } int i = left; int i = left; i left i <= right i right i++ i++ i {
      ans += i;
    } {
      ans += i;
    } ans += i ans i return ans; ans int left left int right right void show(int ans) {
    System.out.println(ans);
  } show {
    System.out.println(ans);
  } System.out.println(ans) System.out.println System.out System System.out ans int ans ans Reader public class Main extends Reader {
  public static void main(String[] args) {
    Main main = new Main();
    main.show(main.solve());
  }

  int n;
  int[] a;

  public Main() {
    n = ini();
    a = vi(n);
  }
  
  int solve() {
    int[] cnt = new int[101];
    for (int i = 0; i < n; i++) {
      cnt[a[i]]++;
    }
    int ans = 0;
    for (int i = 1; i <= 100; i++) {
      if (cnt[i] != 0) ans++;
    }
    return ans;
  }

  int calc(int left, int right) {
    int ans = 0;
    for (int i = left; i <= right; i++) {
      ans += i;
    }
    return ans;
  }

  void show(int ans) {
    System.out.println(ans);
  }
} public class Main extends Reader {
  public static void main(String[] args) {
    Main main = new Main();
    main.show(main.solve());
  }

  int n;
  int[] a;

  public Main() {
    n = ini();
    a = vi(n);
  }
  
  int solve() {
    int[] cnt = new int[101];
    for (int i = 0; i < n; i++) {
      cnt[a[i]]++;
    }
    int ans = 0;
    for (int i = 1; i <= 100; i++) {
      if (cnt[i] != 0) ans++;
    }
    return ans;
  }

  int calc(int left, int right) {
    int ans = 0;
    for (int i = left; i <= right; i++) {
      ans += i;
    }
    return ans;
  }

  void show(int ans) {
    System.out.println(ans);
  }
} Main
import java.util.*;

class Reader {
  Scanner sc = new Scanner(System.in);

  public int ini() {
    return sc.nextInt();
  }

  public int[] vi(int n) {
    int[] a = new int[n];
    for (int i = 0; i < n; i++) a[i] = sc.nextInt();
    return a;
  }
}

public class Main extends Reader {
  public static void main(String[] args) {
    Main main = new Main();
    main.show(main.solve());
  }

  int n;
  int[] a;

  public Main() {
    n = ini();
    a = vi(n);
  }
  
  int solve() {
    int[] cnt = new int[101];
    for (int i = 0; i < n; i++) {
      cnt[a[i]]++;
    }
    int ans = 0;
    for (int i = 1; i <= 100; i++) {
      if (cnt[i] != 0) ans++;
    }
    return ans;
  }

  int calc(int left, int right) {
    int ans = 0;
    for (int i = left; i <= right; i++) {
      ans += i;
    }
    return ans;
  }

  void show(int ans) {
    System.out.println(ans);
  }
}


