import java.util.*;

public class Main {
	public static void main(String[] args) throws Exception{
		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();
		}
      	Arrays.sort(d);
      	int count = 0;
      	for(int i=1; i<n; i++){
          if(d[i]==d[i-1]) count++;
        }
      	System.out.println(n-count);
	}
} import java.util.*; util.* java public class Main {
	public static void main(String[] args) throws Exception{
		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();
		}
      	Arrays.sort(d);
      	int count = 0;
      	for(int i=1; i<n; i++){
          if(d[i]==d[i-1]) count++;
        }
      	System.out.println(n-count);
	}
} Main public static void main(String[] args) throws Exception{
		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();
		}
      	Arrays.sort(d);
      	int count = 0;
      	for(int i=1; i<n; i++){
          if(d[i]==d[i-1]) count++;
        }
      	System.out.println(n-count);
	} main {
		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();
		}
      	Arrays.sort(d);
      	int count = 0;
      	for(int i=1; i<n; i++){
          if(d[i]==d[i-1]) count++;
        }
      	System.out.println(n-count);
	} 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 count = 0; count 0 for(int i=1; i<n; i++){
          if(d[i]==d[i-1]) count++;
        } int i=1; int i=1; i 1 i<n i n i++ i++ i {
          if(d[i]==d[i-1]) count++;
        } {
          if(d[i]==d[i-1]) count++;
        } if(d[i]==d[i-1]) count++; d[i]==d[i-1] d[i] d i d[i-1] d i-1 i 1 count++ count System.out.println(n-count) System.out.println System.out System System.out n-count n count String[] args args public class Main {
	public static void main(String[] args) throws Exception{
		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();
		}
      	Arrays.sort(d);
      	int count = 0;
      	for(int i=1; i<n; i++){
          if(d[i]==d[i-1]) count++;
        }
      	System.out.println(n-count);
	}
} public class Main {
	public static void main(String[] args) throws Exception{
		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();
		}
      	Arrays.sort(d);
      	int count = 0;
      	for(int i=1; i<n; i++){
          if(d[i]==d[i-1]) count++;
        }
      	System.out.println(n-count);
	}
} Main
import java.util.*;

public class Main {
	public static void main(String[] args) throws Exception{
		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();
		}
      	Arrays.sort(d);
      	int count = 0;
      	for(int i=1; i<n; i++){
          if(d[i]==d[i-1]) count++;
        }
      	System.out.println(n-count);
	}
}
