int main () {
	int nombre_partides;
	cin >> nombre_partides;
	for (int i=0; i<nombre_partides; ++i) {
		bool anna=false;
		bool bernat=false;
		vector<string> v(10);
		for (int j=0; j<10; ++j) cin >> v[j];
		for (int j=1; j<10 and not anna and not bernat; ++j) {
			if (v[j-1][v[j-1].size()-1] != v[j][0] and j%2==0) bernat=true;
			if (v[j-1][v[j-1].size()-1] != v[j][0] and j%2!=0) anna=true;
		}
		if (anna) cout << "A" << endl;
		else if (bernat) cout << "B" << endl;
		else cout << "=" << endl;


	}
}