#include <bits/stdc++.h>
using namespace std;
int main() {
vector <int> aux;
vector < vector <int> > lista (110, aux);
int m, n, testes, num;
cin >> testes;
while(testes--){
cin >> m >> n;
for(int i = 0; i < n; i++){
cin >> num;
//cout << num << " : " << num%m << "\n";
lista[num%m].push_back(num);
}
for(int i = 0; i < m; i++){
cout << i << " -> ";
for(int j = 0; j < lista[i].size(); j++){
cout << lista[i][j] << " -> ";
}
cout << "\\" << "\n";
}
if(testes >= 1)
cout << "\n";
for(int i = 0; i < m; i++){
for(int j = 0; j < lista[i].size(); j++){
lista[i].clear();
}
}
}
return 0;
}
