import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        // Write your code here
        Scanner sc = new Scanner(System.in);
        int t = sc.nextInt();
        while(t-- > 0){
            int n = sc.nextInt();
            int[] a = new int[n];
            int[] freq = new int[100001];
            for(int i = 0 ; i < n ; i++){
                a[i] = sc.nextInt();
                freq[a[i]]++;
            }
            int count = 0;
            for(int i = 0 ; i < freq.length ; i++){
                if(freq[i] > 0) count++;
            }
         System.out.println(count);   
        }
    }
}