#include <bits/stdc++.h>
using namespace std;
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int q;
	cin >> q;
	while (q--) {
		int n, m;
		cin >> n >> m;
		vector<vector<int>> g(2 * n);
		auto f = [&](int u1, int v1) {
			g[u1 ^ 1].push_back(v1);
			g[v1 ^ 1].push_back(u1);
		};
		for (int i = 0; i < m; i++) {
			int a, b, e;
			char x, y, z;
			cin >> a >> x >> b >> y >> e >> z;
			int u = (x == 'H' ? 2 * (a - 1) : 2 * (a - 1) + 1);
			int v = (y == 'H' ? 2 * (b - 1) : 2 * (b - 1) + 1);
			int w = (z == 'H' ? 2 * (e - 1) : 2 * (e - 1) + 1);
			f(u, v);
			f(u, w);
			f(v, w);
		}
		vector<int> d(2 * n, 0);
		vector<int> l(2 * n, 0);
		vector<int> s(2 * n, 0);
		vector<bool> k(2 * n, false);
		vector<int> p;
		int r = 0;
		int c = 0;
		auto t = [&](auto self, int u) -> void {
			r++;
			d[u] = l[u] = r;
			p.push_back(u);
			k[u] = true;
			for (int v1 : g[u]) {
				if (!d[v1]) {
					self(self, v1);
					l[u] = min(l[u], l[v1]);
				} else if (k[v1]) {
					l[u] = min(l[u], d[v1]);
				}
			}
			if (l[u] == d[u]) {
				c++;
				while (true) {
					int v1 = p.back();
					p.pop_back();
					k[v1] = false;
					s[v1] = c;
					if (u == v1) {
						break;
					}
				}
			}
		};
		for (int i = 0; i < 2 * n; i++) {
			if (!d[i]) {
				t(t, i);
			}
		}
		bool o = true;
		for (int i = 0; i < n; i++) {
			if (s[2 * i] == s[2 * i + 1]) {
				o = false;
				break;
			}
		}
		if (o) {
			for (int i = 0; i < n; i++) {
				if (i > 0) {
					cout << ' ';
				}
				if (s[2 * i] < s[2 * i + 1]) {
					cout << 'H';
				} else {
					cout << 'T';
				}
			}
			cout << '\n';
		} else {
			cout << -1 << '\n';
		}
	}
	return 0;
}