import collections
import heapq

T = int(input())

def kado():
    N = int(input())
    L = collections.Counter(map(int, input().strip().split(" ")))
    Lv = L.values()
    if len(Lv) < 3:
        return 0
    heap = [-i for i in Lv]
    heapq.heapify(heap)

    total = 0
    while True:
        k1 = heapq.heappop(heap)
        k2 = heapq.heappop(heap)
        k3 = heapq.heappop(heap)
        if k3 == 0:
            break
        total += 1
        heapq.heappush(heap, k1+1)
        heapq.heappush(heap, k2+1)
        heapq.heappush(heap, k3+1)
    return total

print("\n".join([str(kado()) for i in range(T)]))