from collections import Counter
from heapq import heapify, heappop, heappush

for _ in range(int(input())):
    n = int(input())
    A = list(map(int, input().split()))
    counter = Counter(A)
    H = [-cnt for cnt in counter.values()]
    heapify(H)
    ans = 0
    while len(H) >= 3:
        a = -heappop(H)
        b = -heappop(H)
        c = -heappop(H)
        ans += c
        a -= c
        if a > 0:
            heappush(H, -a)
        b -= c
        if b > 0:
            heappush(H, -b)
    print(ans)