/*******************************************
Problem - Data Classification
Solution By - Sean Falconer
*******************************************/

#include <iostream>
#include <iomanip>
using namespace std;

int main() {
	int N, C, A;
	cin >> N;
	for(int i = 0; i < N; i++) {
		double p, prob, answer = INT_MIN;
		int cBest = 1;
		cin >> C >> A;
		for(int j = 0; j < C; j++) {
			cin >> prob;
			for(int k = 0; k < A; k++) {
				cin >> p;
				prob *= p;
			}
			if(answer < prob) {
				answer = prob;
				cBest = j + 1;
			}
		}
		cout << setiosflags(ios::fixed) << setprecision(5);
		cout << "Class " << cBest << " " << answer << endl;
	}

	return 0;
}