# -*- coding:utf-8 -*-
import collections

def solve():
	n = input()
	L = map(int,raw_input().split())
	cnt = collections.Counter(L)
	if len(set(L)) < 3:
		print 0
		return
	no1 = cnt.most_common(1)[0][1]
	if no1 <= n /3:
		print n / 3
	else:
		no2 = cnt.most_common(2)[1][1]
		if no2 > n - no1:
			print n - no1 - no2
		else:
			print (n-no1) / 2

if __name__ == "__main__":
	t = input()
	for i in xrange(t):
		solve()