from collections import defaultdict
for _ in range(int(input())):
    N = int(input())
    L = list(map(int,input().split()))
    dic = defaultdict(int)
    for l in L:
        dic[l] += 1
    cnt = 0
    N3 = N //3
    for v in dic.values():
        if v > N3:
            cnt += v - N3
    print((N - cnt)//3)