import java.util.*;

public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
        int[] diameter;
        int step = 0;
        int massdia = 0;
		
        int cnt = sc.nextInt();
        diameter = new int[cnt];
        
        for(int i = 0; i < cnt; i++){
            diameter[i] = sc.nextInt();
        }
        
        int[] sort;
        sort = Arrays.stream(diameter).distinct().toArray();
        
        
        System.out.println(sort.length);
	}
} import java.util.*; util.* java public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
        int[] diameter;
        int step = 0;
        int massdia = 0;
		
        int cnt = sc.nextInt();
        diameter = new int[cnt];
        
        for(int i = 0; i < cnt; i++){
            diameter[i] = sc.nextInt();
        }
        
        int[] sort;
        sort = Arrays.stream(diameter).distinct().toArray();
        
        
        System.out.println(sort.length);
	}
} Main public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
        int[] diameter;
        int step = 0;
        int massdia = 0;
		
        int cnt = sc.nextInt();
        diameter = new int[cnt];
        
        for(int i = 0; i < cnt; i++){
            diameter[i] = sc.nextInt();
        }
        
        int[] sort;
        sort = Arrays.stream(diameter).distinct().toArray();
        
        
        System.out.println(sort.length);
	} main {
		Scanner sc = new Scanner(System.in);
        int[] diameter;
        int step = 0;
        int massdia = 0;
		
        int cnt = sc.nextInt();
        diameter = new int[cnt];
        
        for(int i = 0; i < cnt; i++){
            diameter[i] = sc.nextInt();
        }
        
        int[] sort;
        sort = Arrays.stream(diameter).distinct().toArray();
        
        
        System.out.println(sort.length);
	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int[] diameter; diameter int step = 0; step 0 int massdia = 0; massdia 0 int cnt = sc.nextInt(); cnt sc.nextInt() sc.nextInt sc diameter = new int[cnt] diameter new int[cnt] cnt for(int i = 0; i < cnt; i++){
            diameter[i] = sc.nextInt();
        } int i = 0; int i = 0; i 0 i < cnt i cnt i++ i++ i {
            diameter[i] = sc.nextInt();
        } {
            diameter[i] = sc.nextInt();
        } diameter[i] = sc.nextInt() diameter[i] diameter i sc.nextInt() sc.nextInt sc int[] sort; sort sort = Arrays.stream(diameter).distinct().toArray() sort Arrays.stream(diameter).distinct().toArray() Arrays.stream(diameter).distinct().toArray Arrays.stream(diameter).distinct() Arrays.stream(diameter).distinct Arrays.stream(diameter) Arrays.stream Arrays diameter System.out.println(sort.length) System.out.println System.out System System.out sort.length sort sort.length String[] args args public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
        int[] diameter;
        int step = 0;
        int massdia = 0;
		
        int cnt = sc.nextInt();
        diameter = new int[cnt];
        
        for(int i = 0; i < cnt; i++){
            diameter[i] = sc.nextInt();
        }
        
        int[] sort;
        sort = Arrays.stream(diameter).distinct().toArray();
        
        
        System.out.println(sort.length);
	}
} public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
        int[] diameter;
        int step = 0;
        int massdia = 0;
		
        int cnt = sc.nextInt();
        diameter = new int[cnt];
        
        for(int i = 0; i < cnt; i++){
            diameter[i] = sc.nextInt();
        }
        
        int[] sort;
        sort = Arrays.stream(diameter).distinct().toArray();
        
        
        System.out.println(sort.length);
	}
} Main
import java.util.*;

public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
        int[] diameter;
        int step = 0;
        int massdia = 0;
		
        int cnt = sc.nextInt();
        diameter = new int[cnt];
        
        for(int i = 0; i < cnt; i++){
            diameter[i] = sc.nextInt();
        }
        
        int[] sort;
        sort = Arrays.stream(diameter).distinct().toArray();
        
        
        System.out.println(sort.length);
	}
}