from collections import *
from heapq import *
T = int(input())
for _ in range(T):
    N = int(input())
    L = list(map(int, input().split()))
    D = defaultdict(int)
    for a in L:
        D[a] += 1
    H = []
    for k, v in D.items():
        heappush(H, -v)
        
    ans = 0
    while len(H) >= 3:
        a = heappop(H)
        b = heappop(H)
        c = heappop(H)
        a, b, c = -a - 1, -b - 1, -c - 1
        ans += 1
        if a:
            heappush(H, -a)
        if b:
            heappush(H, -b)
        if c:
            heappush(H, -c)
    print(ans)