import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int t = sc.nextInt();
        StringBuilder sb = new StringBuilder();
        for (int j = 0; j < t; j++) {
            int n = sc.nextInt();
            HashMap<Integer, Integer> map = new HashMap<>();
            int max = 1;
            for (int i= 0; i < n; i++) {
                int x = sc.nextInt();
                if (map.containsKey(x)) {
                    map.put(x, map.get(x) + 1);
                    max = Math.max(max, map.get(x));
                } else {
                    map.put(x, 1);
                }
            }
            sb.append(Math.min(n / 3, (n - max) / 2)).append("\n");
        }
        System.out.print(sb);
    }
}