import java.util.*;
 
public class Main{
  public static void main(String[]args){
    Scanner sc = new Scanner(System.in);
    int N = Integer.parseInt(sc.nextLine());
    Set<Integer> set = new HashSet<>();
    for(int i = 0; i < N; i++){
      int M = Integer.parseInt(sc.nextLine());
      set.add(M);
    }
    System.out.println(set.size());
  }
} import java.util.*; util.* java public class Main{
  public static void main(String[]args){
    Scanner sc = new Scanner(System.in);
    int N = Integer.parseInt(sc.nextLine());
    Set<Integer> set = new HashSet<>();
    for(int i = 0; i < N; i++){
      int M = Integer.parseInt(sc.nextLine());
      set.add(M);
    }
    System.out.println(set.size());
  }
} Main public static void main(String[]args){
    Scanner sc = new Scanner(System.in);
    int N = Integer.parseInt(sc.nextLine());
    Set<Integer> set = new HashSet<>();
    for(int i = 0; i < N; i++){
      int M = Integer.parseInt(sc.nextLine());
      set.add(M);
    }
    System.out.println(set.size());
  } main {
    Scanner sc = new Scanner(System.in);
    int N = Integer.parseInt(sc.nextLine());
    Set<Integer> set = new HashSet<>();
    for(int i = 0; i < N; i++){
      int M = Integer.parseInt(sc.nextLine());
      set.add(M);
    }
    System.out.println(set.size());
  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int N = Integer.parseInt(sc.nextLine()); N Integer.parseInt(sc.nextLine()) Integer.parseInt Integer sc.nextLine() sc.nextLine sc Set<Integer> set = new HashSet<>(); set new HashSet<>() for(int i = 0; i < N; i++){
      int M = Integer.parseInt(sc.nextLine());
      set.add(M);
    } int i = 0; int i = 0; i 0 i < N i N i++ i++ i {
      int M = Integer.parseInt(sc.nextLine());
      set.add(M);
    } {
      int M = Integer.parseInt(sc.nextLine());
      set.add(M);
    } int M = Integer.parseInt(sc.nextLine()); M Integer.parseInt(sc.nextLine()) Integer.parseInt Integer sc.nextLine() sc.nextLine sc set.add(M) set.add set M System.out.println(set.size()) System.out.println System.out System System.out set.size() set.size set String[]args args public class Main{
  public static void main(String[]args){
    Scanner sc = new Scanner(System.in);
    int N = Integer.parseInt(sc.nextLine());
    Set<Integer> set = new HashSet<>();
    for(int i = 0; i < N; i++){
      int M = Integer.parseInt(sc.nextLine());
      set.add(M);
    }
    System.out.println(set.size());
  }
} public class Main{
  public static void main(String[]args){
    Scanner sc = new Scanner(System.in);
    int N = Integer.parseInt(sc.nextLine());
    Set<Integer> set = new HashSet<>();
    for(int i = 0; i < N; i++){
      int M = Integer.parseInt(sc.nextLine());
      set.add(M);
    }
    System.out.println(set.size());
  }
} Main
import java.util.*;
 
public class Main{
  public static void main(String[]args){
    Scanner sc = new Scanner(System.in);
    int N = Integer.parseInt(sc.nextLine());
    Set<Integer> set = new HashSet<>();
    for(int i = 0; i < N; i++){
      int M = Integer.parseInt(sc.nextLine());
      set.add(M);
    }
    System.out.println(set.size());
  }
}