#include <iostream>
#include <sstream>
#include <math.h>
#include <vector>
#include <array>
#include <algorithm>
#include <queue>
#include <numeric>
#include <map>
#include <set>

using namespace std;
#define int long long
#define FOR(i, a, b) for(int i=(a);i<(b);i++)
#define RFOR(i, a, b) for(int i=(b-1);i>=(a);i--)
#define REP(i, n) for(int i=0; i<(n); i++)
#define RREP(i, n) for(int i=(n-1); i>=0; i--)
#define ALL(a) (a).begin(),(a).end()
#define UNIQUE_SORT(l) sort(ALL(l)); l.erase(unique(ALL(l)), l.end());
#define CONTAIN(a, b) find(ALL(a), (b)) != (a).end()
#define SUM(a) accumulate(ALL(a), 0)
#define array2(type, x, y) array<array<type, y>, x>
#define vector2(type) vector<vector<type> >
#define out(...) printf(__VA_ARGS__)

typedef pair<int, int> pos;
int pos::*x = &pos::first;
int pos::*y = &pos::second;

int dxy[] = {0, 1, 0, -1, 0};

/*================================*/

int T, N;

signed main()
{
    cin >> T;
    vector<int> ans;
    REP(t,T) {
        cin >> N;
        int maxN = N / 3; // 個数から考える最大数
        int l;
        map<int, int> take;
        REP(i,N) {
            cin >> l;
            take[l]++;
        }
        vector<int> values;
        for(auto& kv : take) {
            values.push_back(kv.second);
        }
        sort(ALL(values));
        int remain = N;
        REP(i,2) {
            int lasti = values.size() - 1;
            if (0 <= lasti - i) {
                remain -= values[lasti - i];
            }
        }
        int maxK = remain; // 竹の種類から考える最大数
        ans.push_back(max(min(maxK, maxN), (int)0));
    }
    REP(i,ans.size()) cout << ans[i] << endl;
    return 0;
}