import java.util.*;

public class Main {

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

} import java.util.*; util.* java public class Main {

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

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

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

} public class Main {

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

} Main
import java.util.*;

public class Main {

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

}