#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// using namespace __gnu_pbds;
using namespace std;

#define int           long long
#define ul            unsigned long long
#define ld            long double
const int mod =       1e9 + 7;
const int inf =       LLONG_MAX;
const int dif =       1e-9;
#define vi            vector<int>
#define vs            vector<string>
#define pii           pair<int, int>
#define ump           unordered_map
#define pq_max        priority_queue<int>
#define pq_min        priority_queue<int, vi, greater<int>>
#define ff            first
#define ss            second
#define pb            emplace_back
#define pf            push_front
#define pbb           pop_back
#define pff           pop_front
#define loop(i, a, b) for(int i = a; i < b; ++i)
#define rev(i, a, b)  for(int i = a; i >= b; --i)
#define uniq(v)       (v).erase(unique(all(v)),(v).end())
#define bs(v,a)       binary_search(all(v), a)
#define uprb(v,a)     upper_bound(v.begin(), v.end(), a)
#define lowb(v,a)     lower_bound(v.begin(), v.end(), a)
#define all(x)        x.begin(), x.end()
#define ps(x, y)      fixed << setprecision(y) << x
#define range(a, b)   substr(a, b - a + 1)
#define log(x) 	      cout << #x << " : " << x << " " << '\n';
#define lcm(a,b)      ((a)*(b)) / __gcd((a),(b))
#define setbits(n)    __builtin_popcountll(n)
#define zerobits(n)   __builtin_ctzll(n)
static mt19937        rng(chrono::steady_clock::now().time_since_epoch().count());

// typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> pbds;

int freq[102];
vi v;

void solve() {
	int n;
	cin >> n;

	memset(freq, 0, sizeof freq);

	for (int i = 0; i < n; ++i) {
		int x; cin >> x;
		freq[x]++;
	}

	loop(i, 0, 102) {
		if (freq[i]) {
			cout << i << ' ';
			freq[i]--;
		}

		while (freq[i]) {
			v.pb(i);
			freq[i]--;
		}
	}

	for (auto &i : v)
		cout << i << ' ';

	cout << '\n';
	v.clear();
}

signed main() {
	clock_t begin = clock();
	ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);


	int t = 1;
	cin >> t;

	while (t--) {
		solve();
	}


#ifndef ONLINE_JUDGE
	clock_t end = clock();
	cout << "\n\nExecuted In: " << double(end - begin) / CLOCKS_PER_SEC * 1000 << " ms";
#endif
	return 0;
}