# 3つの数が異なれば門松列は作れる
# ある数が多数ある場合はそれから使うのがいい

T = int(input())
for t in range(T):
    N = int(input())
    L = list(map(int, input().split()))
    from collections import Counter
    counted = Counter(L)
    from heapq import *
    H = []
    heapify(H)
    for n in counted:
        heappush(H, -counted[n])
    ans = 0
    while True:
        if len(H) < 3:
            break
        else:
            k1 = heappop(H)
            k2 = heappop(H)
            k3 = heappop(H)
            ans += 1
            if k1 < -1:
                heappush(H, k1+1)
            if k2 < -1:
                heappush(H, k2+1)
            if k3 < -1:
                heappush(H, k3+1)
        #print('ans', ans, 'H', H)
    print(ans)