import java.util.*;

class Main {
	public static void main(String[] args) {
		//data nyuroku
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int d[] = new int[N];
		for (int i=0;i<N;i++) {
			d[i] = sc.nextInt();
		}
		//sort
		Arrays.sort(d);
		//mochimochi
		int n=N;
		for(int i=0;i<N-1;i++) {
			if (d[i]==d[i+1]) {
				n--;
			}
		}
		System.out.println(n);
	}
} import java.util.*; util.* java class Main {
	public static void main(String[] args) {
		//data nyuroku
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int d[] = new int[N];
		for (int i=0;i<N;i++) {
			d[i] = sc.nextInt();
		}
		//sort
		Arrays.sort(d);
		//mochimochi
		int n=N;
		for(int i=0;i<N-1;i++) {
			if (d[i]==d[i+1]) {
				n--;
			}
		}
		System.out.println(n);
	}
} Main public static void main(String[] args) {
		//data nyuroku
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int d[] = new int[N];
		for (int i=0;i<N;i++) {
			d[i] = sc.nextInt();
		}
		//sort
		Arrays.sort(d);
		//mochimochi
		int n=N;
		for(int i=0;i<N-1;i++) {
			if (d[i]==d[i+1]) {
				n--;
			}
		}
		System.out.println(n);
	} main {
		//data nyuroku
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int d[] = new int[N];
		for (int i=0;i<N;i++) {
			d[i] = sc.nextInt();
		}
		//sort
		Arrays.sort(d);
		//mochimochi
		int n=N;
		for(int i=0;i<N-1;i++) {
			if (d[i]==d[i+1]) {
				n--;
			}
		}
		System.out.println(n);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int N = sc.nextInt(); N sc.nextInt() sc.nextInt sc int d[] = new int[N]; d new int[N] N for (int i=0;i<N;i++) {
			d[i] = sc.nextInt();
		} int i=0; int i=0; i 0 i<N i N i++ i++ i {
			d[i] = sc.nextInt();
		} {
			d[i] = sc.nextInt();
		} d[i] = sc.nextInt() d[i] d i sc.nextInt() sc.nextInt sc Arrays.sort(d) Arrays.sort Arrays d int n=N; n N for(int i=0;i<N-1;i++) {
			if (d[i]==d[i+1]) {
				n--;
			}
		} int i=0; int i=0; i 0 i<N-1 i N-1 N 1 i++ i++ i {
			if (d[i]==d[i+1]) {
				n--;
			}
		} {
			if (d[i]==d[i+1]) {
				n--;
			}
		} if (d[i]==d[i+1]) {
				n--;
			} d[i]==d[i+1] d[i] d i d[i+1] d i+1 i 1 {
				n--;
			} n-- n System.out.println(n) System.out.println System.out System System.out n String[] args args
import java.util.*;

class Main {
	public static void main(String[] args) {
		//data nyuroku
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int d[] = new int[N];
		for (int i=0;i<N;i++) {
			d[i] = sc.nextInt();
		}
		//sort
		Arrays.sort(d);
		//mochimochi
		int n=N;
		for(int i=0;i<N-1;i++) {
			if (d[i]==d[i+1]) {
				n--;
			}
		}
		System.out.println(n);
	}
}