#include <bits/stdc++.h>

// author: @noisegain

#define db1(x) cout << #x << "=" << x << '\n'
#define db2(x, y) cout << #x << "=" << x << "," << #y << "=" << y << '\n'
#define db3(x, y, z)                                                       \
  cout << #x << "=" << x << "," << #y << "=" << y << "," << #z << "=" << z \
       << '\n'
#define all(arr) (arr).begin(), (arr).end()
#define rall(arr) (arr).rbegin(), (arr).rend()
#define len(a) (int)(a.size())
#define un(a) a.resize(unique(all(a)) - a.begin())
#define time_(x) cout << (clock() - x) * 1.0 / CLOCKS_PER_SEC << endl
#define inout0                      \
  ios_base::sync_with_stdio(false); \
  cin.tie(0);                       \
  cout.tie(0)

using ll = long long;
using ld = long double;
using ull = unsigned long long;
using namespace std;

template <typename T>
istream& operator>>(istream& in, vector<T>& v) {
    for (auto& i : v) in >> i;
    return in;
}

template <typename T>
ostream& operator<<(ostream& out, vector<T>& v) {
    if (is_same<T, pair<int, int>>::value) {
        for (auto& i : v) out << i << endl;
    } else {
        for (auto& i : v) out << i << " ";
    }
    return out;
}

template <typename T, typename V>
ostream& operator<<(ostream& out, pair<T, V>& v) {
    out << v.first << " " << v.second;
    return out;
}

template <typename T, typename V>
istream& operator>>(istream& in, pair<T, V>& v) {
    in >> v.first >> v.second;
    return in;
}

void solve() {
    int n;
    cin >> n;
    vector<int> a(n);
    cin >> a;
    sort(rall(a));
    vector<int> a1, a2;
    a1.push_back(a.back());
    a.erase(a.end() - 1);
    while (--n) {
        if (a1.back() == a.back()) {
            a2.push_back(a.back());
        } else {
            a1.push_back(a.back());
        }
        a.erase(a.end() - 1);
    }
    cout << a1 << a2 << endl;
}

int main() {
    int t;
    cin >> t;
    while (t--) solve();
}