def solve():
    n = int(input())
    L = list(map(int, input().split()))
    cnt = {}
    for l in L:
        cnt[l] = cnt.get(l, 0) + 1
    ans = 0
    V = list(cnt.values())
    
    l = 0
    r = n // 3 + 1
    while r - l > 1:
        mid = (l + r) // 2
        c = sum(min(v, mid) for v in V)
        if c >= 3 * mid:
            l = mid
        else:
            r = mid
    print(l)

for _ in range(int(input())):
    solve()