import java.util.Scanner;
import java.util.Arrays;
public class Main {
  public static void main (String[]args) {
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    int stage = N;
    int di[] = new int[N];

    for(int i = 0; i<N; i++){ //とりあえず配列に全部代入
      di[i] = sc.nextInt();
    }

    Arrays.sort(di);//ソート（昇順）

    for(int i =0; i<N; i++ ) {
      if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      }
    }
    System.out.println(stage);
  }
} import java.util.Scanner; Scanner java.util import java.util.Arrays; Arrays java.util public class Main {
  public static void main (String[]args) {
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    int stage = N;
    int di[] = new int[N];

    for(int i = 0; i<N; i++){ //とりあえず配列に全部代入
      di[i] = sc.nextInt();
    }

    Arrays.sort(di);//ソート（昇順）

    for(int i =0; i<N; i++ ) {
      if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      }
    }
    System.out.println(stage);
  }
} Main public static void main (String[]args) {
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    int stage = N;
    int di[] = new int[N];

    for(int i = 0; i<N; i++){ //とりあえず配列に全部代入
      di[i] = sc.nextInt();
    }

    Arrays.sort(di);//ソート（昇順）

    for(int i =0; i<N; i++ ) {
      if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      }
    }
    System.out.println(stage);
  } main {
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    int stage = N;
    int di[] = new int[N];

    for(int i = 0; i<N; i++){ //とりあえず配列に全部代入
      di[i] = sc.nextInt();
    }

    Arrays.sort(di);//ソート（昇順）

    for(int i =0; i<N; i++ ) {
      if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      }
    }
    System.out.println(stage);
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int N = sc.nextInt(); N sc.nextInt() sc.nextInt sc int stage = N; stage N int di[] = new int[N]; di new int[N] N for(int i = 0; i<N; i++){ //とりあえず配列に全部代入
      di[i] = sc.nextInt();
    } int i = 0; int i = 0; i 0 i<N i N i++ i++ i { //とりあえず配列に全部代入
      di[i] = sc.nextInt();
    } { //とりあえず配列に全部代入
      di[i] = sc.nextInt();
    } di[i] = sc.nextInt() di[i] di i sc.nextInt() sc.nextInt sc Arrays.sort(di) Arrays.sort Arrays di for(int i =0; i<N; i++ ) {
      if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      }
    } int i =0; int i =0; i 0 i<N i N i++ i++ i {
      if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      }
    } {
      if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      }
    } if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      } i != N-1 i N-1 N 1 {
        if(di[i] == di[i+1]){
          stage--;
        }
      } if(di[i] == di[i+1]){
          stage--;
        } di[i] == di[i+1] di[i] di i di[i+1] di i+1 i 1 {
          stage--;
        } stage-- stage System.out.println(stage) System.out.println System.out System System.out stage String[]args args public class Main {
  public static void main (String[]args) {
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    int stage = N;
    int di[] = new int[N];

    for(int i = 0; i<N; i++){ //とりあえず配列に全部代入
      di[i] = sc.nextInt();
    }

    Arrays.sort(di);//ソート（昇順）

    for(int i =0; i<N; i++ ) {
      if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      }
    }
    System.out.println(stage);
  }
} public class Main {
  public static void main (String[]args) {
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    int stage = N;
    int di[] = new int[N];

    for(int i = 0; i<N; i++){ //とりあえず配列に全部代入
      di[i] = sc.nextInt();
    }

    Arrays.sort(di);//ソート（昇順）

    for(int i =0; i<N; i++ ) {
      if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      }
    }
    System.out.println(stage);
  }
} Main
import java.util.Scanner;
import java.util.Arrays;
public class Main {
  public static void main (String[]args) {
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    int stage = N;
    int di[] = new int[N];

    for(int i = 0; i<N; i++){ //とりあえず配列に全部代入
      di[i] = sc.nextInt();
    }

    Arrays.sort(di);//ソート（昇順）

    for(int i =0; i<N; i++ ) {
      if(i != N-1) {
        if(di[i] == di[i+1]){
          stage--;
        }
      }
    }
    System.out.println(stage);
  }
}
