// NOTE: it is recommended to use this even if you don't understand the following code.

#include <fstream>
#include <iostream>
#include <string>
#include <vector>

using namespace std;

int main() {
    // uncomment the two following lines if you want to read/write from files
    // ifstream cin("input.txt");
    // ofstream cout("output.txt");

    int T;
    cin >> T;
    for (int test = 1; test <= T; ++test) {
        int N;
        cin >> N;

        vector<int> A(N), B(N), C(N);
        for (int i = 0; i < N; ++i)
            cin >> A[i] >> B[i] >> C[i];

        int M = 0;
        vector<int> R(M);


        // INSERT YOUR CODE HERE


        cout << M << endl;
        for (int i = 0; i < M; ++i)
            cout << R[i] << " ";
        cout << endl;
    }

    return 0;
}