T = int(input())
from collections import defaultdict

def f(d,mid):
    tmp = 0
    for i in d:
        v = d[i]
        tmp += min(mid,v)
    return tmp >= 3 * mid
def calc(l):
    N = len(l)
    if N <= 2:
        return 0
    d = defaultdict(int)
    for i in l:
        d[i] += 1
    start = 0
    end = N
    while end - start > 1:
        mid = end + start >> 1
        if f(d,mid):
            start = mid
        else:
            end = mid
    return start
for _ in range(T):
    N = int(input())
    l = list(map(int,input().split()))
    print(calc(l))