import java.util.Arrays;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
	int n=sc.nextInt();
	int a[]=new int[n];
	for(int i=0;i<=n-1;i++){
		a[i]=sc.nextInt();
	}
Arrays.sort(a);
int sam=0;
for(int i=0;i<=n-2;i++){
if(a[i]==a[i+1]){
	sam++;
}
}System.out.println(n-sam);
	}} import java.util.Arrays; Arrays java.util import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
	int n=sc.nextInt();
	int a[]=new int[n];
	for(int i=0;i<=n-1;i++){
		a[i]=sc.nextInt();
	}
Arrays.sort(a);
int sam=0;
for(int i=0;i<=n-2;i++){
if(a[i]==a[i+1]){
	sam++;
}
}System.out.println(n-sam);
	}} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
	int n=sc.nextInt();
	int a[]=new int[n];
	for(int i=0;i<=n-1;i++){
		a[i]=sc.nextInt();
	}
Arrays.sort(a);
int sam=0;
for(int i=0;i<=n-2;i++){
if(a[i]==a[i+1]){
	sam++;
}
}System.out.println(n-sam);
	} main {
		Scanner sc = new Scanner(System.in);
	int n=sc.nextInt();
	int a[]=new int[n];
	for(int i=0;i<=n-1;i++){
		a[i]=sc.nextInt();
	}
Arrays.sort(a);
int sam=0;
for(int i=0;i<=n-2;i++){
if(a[i]==a[i+1]){
	sam++;
}
}System.out.println(n-sam);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int n=sc.nextInt(); n sc.nextInt() sc.nextInt sc int a[]=new int[n]; a new int[n] n for(int i=0;i<=n-1;i++){
		a[i]=sc.nextInt();
	} int i=0; int i=0; i 0 i<=n-1 i n-1 n 1 i++ i++ i {
		a[i]=sc.nextInt();
	} {
		a[i]=sc.nextInt();
	} a[i]=sc.nextInt() a[i] a i sc.nextInt() sc.nextInt sc Arrays.sort(a) Arrays.sort Arrays a int sam=0; sam 0 for(int i=0;i<=n-2;i++){
if(a[i]==a[i+1]){
	sam++;
}
} int i=0; int i=0; i 0 i<=n-2 i n-2 n 2 i++ i++ i {
if(a[i]==a[i+1]){
	sam++;
}
} {
if(a[i]==a[i+1]){
	sam++;
}
} if(a[i]==a[i+1]){
	sam++;
} a[i]==a[i+1] a[i] a i a[i+1] a i+1 i 1 {
	sam++;
} sam++ sam System.out.println(n-sam) System.out.println System.out System System.out n-sam n sam String[] args args public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
	int n=sc.nextInt();
	int a[]=new int[n];
	for(int i=0;i<=n-1;i++){
		a[i]=sc.nextInt();
	}
Arrays.sort(a);
int sam=0;
for(int i=0;i<=n-2;i++){
if(a[i]==a[i+1]){
	sam++;
}
}System.out.println(n-sam);
	}} public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
	int n=sc.nextInt();
	int a[]=new int[n];
	for(int i=0;i<=n-1;i++){
		a[i]=sc.nextInt();
	}
Arrays.sort(a);
int sam=0;
for(int i=0;i<=n-2;i++){
if(a[i]==a[i+1]){
	sam++;
}
}System.out.println(n-sam);
	}} Main
import java.util.Arrays;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
	int n=sc.nextInt();
	int a[]=new int[n];
	for(int i=0;i<=n-1;i++){
		a[i]=sc.nextInt();
	}
Arrays.sort(a);
int sam=0;
for(int i=0;i<=n-2;i++){
if(a[i]==a[i+1]){
	sam++;
}
}System.out.println(n-sam);
	}}