import java.lang.reflect.Array;
import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        ArrayList<Integer> arr = new ArrayList<Integer>();
        for(int i=0;i<n;i++)arr.add(sc.nextInt());
        Collections.sort(arr);
        int pre = 0, ans = 0;
        for(int i=0;i<n;i++) {
            if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            }
        }
        System.out.println(ans);
    }
} import java.lang.reflect.Array; Array java.lang.reflect import java.util.*; util.* java public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        ArrayList<Integer> arr = new ArrayList<Integer>();
        for(int i=0;i<n;i++)arr.add(sc.nextInt());
        Collections.sort(arr);
        int pre = 0, ans = 0;
        for(int i=0;i<n;i++) {
            if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            }
        }
        System.out.println(ans);
    }
} Main public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        ArrayList<Integer> arr = new ArrayList<Integer>();
        for(int i=0;i<n;i++)arr.add(sc.nextInt());
        Collections.sort(arr);
        int pre = 0, ans = 0;
        for(int i=0;i<n;i++) {
            if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            }
        }
        System.out.println(ans);
    } main {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        ArrayList<Integer> arr = new ArrayList<Integer>();
        for(int i=0;i<n;i++)arr.add(sc.nextInt());
        Collections.sort(arr);
        int pre = 0, ans = 0;
        for(int i=0;i<n;i++) {
            if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            }
        }
        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 ArrayList<Integer> arr = new ArrayList<Integer>(); arr new ArrayList<Integer>() for(int i=0;i<n;i++)arr.add(sc.nextInt()); int i=0; int i=0; i 0 i<n i n i++ i++ i arr.add(sc.nextInt()); arr.add(sc.nextInt()) arr.add arr sc.nextInt() sc.nextInt sc Collections.sort(arr) Collections.sort Collections arr int pre = 0 pre 0 ans = 0; ans 0 for(int i=0;i<n;i++) {
            if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            }
        } int i=0; int i=0; i 0 i<n i n i++ i++ i {
            if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            }
        } {
            if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            }
        } if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            } arr.get(i) != pre arr.get(i) arr.get arr i pre {
                pre = arr.get(i);
                ans += 1;
            } pre = arr.get(i) pre arr.get(i) arr.get arr i ans += 1 ans 1 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();
        ArrayList<Integer> arr = new ArrayList<Integer>();
        for(int i=0;i<n;i++)arr.add(sc.nextInt());
        Collections.sort(arr);
        int pre = 0, ans = 0;
        for(int i=0;i<n;i++) {
            if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            }
        }
        System.out.println(ans);
    }
} public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        ArrayList<Integer> arr = new ArrayList<Integer>();
        for(int i=0;i<n;i++)arr.add(sc.nextInt());
        Collections.sort(arr);
        int pre = 0, ans = 0;
        for(int i=0;i<n;i++) {
            if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            }
        }
        System.out.println(ans);
    }
} Main
import java.lang.reflect.Array;
import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        ArrayList<Integer> arr = new ArrayList<Integer>();
        for(int i=0;i<n;i++)arr.add(sc.nextInt());
        Collections.sort(arr);
        int pre = 0, ans = 0;
        for(int i=0;i<n;i++) {
            if (arr.get(i) != pre) {
                pre = arr.get(i);
                ans += 1;
            }
        }
        System.out.println(ans);
    }
}