#include <iostream>
#include <vector>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <string>
#include <deque>
#include <algorithm>
#include <cassert>
#include <random>

using namespace std;


unordered_map<string, int> pref;
string ksl[30001];
char ans[30001];


string getst(string cur, int i, int j) {
	string ans = "";
	ans += cur.substr(0, i);
	ans += cur.substr(i + 1, j - (i + 1));
	ans += cur.substr(j + 1, (int)cur.size() - (j + 1));
	return ans;
}


signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	int t;
	cin >> t;
	for (int ccc = 0; ccc < t; ++ccc) {
		int n, k;
		cin >> n >> k;
		string s;
		for (int i = 0; i < n; ++i) {
			cin >> s;
			ksl[i] = s;
		}
		if (k >= 17) {
			for (int i = 0; i < n; ++i) {
				for (int j = i + 1; j < n; ++j) {
					int gg = 0;
					for (int d = 0; d < k; ++d) {
						gg += (ksl[j][d] != ksl[i][d]);
					}
					if (gg <= 2) {
						ans[i] = 1;
						ans[j] = 1;
					}
				}
			}
		}
		else {
			for (int i = 0; i < k - 1; ++i) {
				for (int j = i + 1; j < k; ++j) {
					for (int pos = 0; pos < n; ++pos) {
						string cur = getst(ksl[pos], i, j);
						if (pref.find(cur) != pref.end()) {
							ans[pos] = 1;
							ans[pref[cur]] = 1;
						}
						else {
							pref[cur] = pos;
						}
					}
					pref.clear();
				}
			}
		}
		for (int i = 0; i < n; i++)
			cout << ans[i];
		for (int i = 0; i < n; i++)
			ans[i] = 0;
		cout << '\n';
	}
	return 0;
}