import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashSet;
import java.util.Set;

public class Main {

	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		int N = Integer.parseInt(br.readLine());
		Set<Integer> d = new HashSet<>();

		for (int i = 0; i < N; i++) {
			d.add(Integer.parseInt(br.readLine()));
		}

		System.out.println(d.size());
	}

} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.InputStreamReader; InputStreamReader java.io import java.util.HashSet; HashSet java.util import java.util.Set; Set java.util public class Main {

	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		int N = Integer.parseInt(br.readLine());
		Set<Integer> d = new HashSet<>();

		for (int i = 0; i < N; i++) {
			d.add(Integer.parseInt(br.readLine()));
		}

		System.out.println(d.size());
	}

} Main public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		int N = Integer.parseInt(br.readLine());
		Set<Integer> d = new HashSet<>();

		for (int i = 0; i < N; i++) {
			d.add(Integer.parseInt(br.readLine()));
		}

		System.out.println(d.size());
	} main {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		int N = Integer.parseInt(br.readLine());
		Set<Integer> d = new HashSet<>();

		for (int i = 0; i < N; i++) {
			d.add(Integer.parseInt(br.readLine()));
		}

		System.out.println(d.size());
	} BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); br new BufferedReader(new InputStreamReader(System.in)) int N = Integer.parseInt(br.readLine()); N Integer.parseInt(br.readLine()) Integer.parseInt Integer br.readLine() br.readLine br Set<Integer> d = new HashSet<>(); d new HashSet<>() for (int i = 0; i < N; i++) {
			d.add(Integer.parseInt(br.readLine()));
		} int i = 0; int i = 0; i 0 i < N i N i++ i++ i {
			d.add(Integer.parseInt(br.readLine()));
		} {
			d.add(Integer.parseInt(br.readLine()));
		} d.add(Integer.parseInt(br.readLine())) d.add d Integer.parseInt(br.readLine()) Integer.parseInt Integer br.readLine() br.readLine br System.out.println(d.size()) System.out.println System.out System System.out d.size() d.size d String[] args args public class Main {

	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		int N = Integer.parseInt(br.readLine());
		Set<Integer> d = new HashSet<>();

		for (int i = 0; i < N; i++) {
			d.add(Integer.parseInt(br.readLine()));
		}

		System.out.println(d.size());
	}

} public class Main {

	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		int N = Integer.parseInt(br.readLine());
		Set<Integer> d = new HashSet<>();

		for (int i = 0; i < N; i++) {
			d.add(Integer.parseInt(br.readLine()));
		}

		System.out.println(d.size());
	}

} Main
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashSet;
import java.util.Set;

public class Main {

	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		int N = Integer.parseInt(br.readLine());
		Set<Integer> d = new HashSet<>();

		for (int i = 0; i < N; i++) {
			d.add(Integer.parseInt(br.readLine()));
		}

		System.out.println(d.size());
	}

}
