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

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		Set<Integer>  mochi = new HashSet<>();
		
		while (sc.hasNext()) {
			mochi.add(sc.nextInt());
		}
		System.out.println(mochi.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 sc = new Scanner(System.in);
		int n = sc.nextInt();
		Set<Integer>  mochi = new HashSet<>();
		
		while (sc.hasNext()) {
			mochi.add(sc.nextInt());
		}
		System.out.println(mochi.size());
	}
} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		Set<Integer>  mochi = new HashSet<>();
		
		while (sc.hasNext()) {
			mochi.add(sc.nextInt());
		}
		System.out.println(mochi.size());
	} main {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		Set<Integer>  mochi = new HashSet<>();
		
		while (sc.hasNext()) {
			mochi.add(sc.nextInt());
		}
		System.out.println(mochi.size());
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc Set<Integer>  mochi = new HashSet<>(); mochi new HashSet<>() while (sc.hasNext()) {
			mochi.add(sc.nextInt());
		} sc.hasNext() sc.hasNext sc {
			mochi.add(sc.nextInt());
		} mochi.add(sc.nextInt()) mochi.add mochi sc.nextInt() sc.nextInt sc System.out.println(mochi.size()) System.out.println System.out System System.out mochi.size() mochi.size mochi String[] args args public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		Set<Integer>  mochi = new HashSet<>();
		
		while (sc.hasNext()) {
			mochi.add(sc.nextInt());
		}
		System.out.println(mochi.size());
	}
} public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		Set<Integer>  mochi = new HashSet<>();
		
		while (sc.hasNext()) {
			mochi.add(sc.nextInt());
		}
		System.out.println(mochi.size());
	}
} Main
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		Set<Integer>  mochi = new HashSet<>();
		
		while (sc.hasNext()) {
			mochi.add(sc.nextInt());
		}
		System.out.println(mochi.size());
	}
}
