import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

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

public class Main {
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		int n = Integer.parseInt(scanner.nextLine());
		Set<Integer> s = new HashSet<>();
		for (int i = 0; i < n; i++) {
			s.add(Integer.parseInt(scanner.nextLine()));
		}
		System.out.println(s.size());
	}
}