/* name: D
 * author: 5ab
 * created at: 2023-12-18
 */
#include <iostream>
#include <vector>
using namespace std;

#define all(x) (x).begin(), (x).end()
#define ssz(x) (int((x).size()))

auto chmax = [](auto& x, auto y) { if (x < y) x = y; };
auto chmin = [](auto& x, auto y) { if (y < x) x = y; };

using ll = long long;
const int max_n = 1e3, max_m = max_n * (max_n - 1) / 2;

int l[max_m];

signed main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	
	int cas, n, m;
	
	auto nxt = [&](int x) { return x == n - 2 ? 0 : x + 1; };
	auto prv = [&](int x) { return x == 0 ? n - 2 : x - 1; };
	
	cin >> cas;
	for (int t = 0; t < cas; t++)
	{
		cin >> n >> m;
		for (int i = 0; i < m; i++)
			cin >> l[i];
		
		int curp = 0, curc = 0;
		auto addp = [&](int x) {
			cout << x + 1 << " ";
			if (curc == l[curp])
			{
				cout << "\n" << x + 1 << " ";
				curc = 1, curp++;
			}
			else
				curc++;
		};
		
		cout << "Case #" << t + 1 << ":\n";
		for (int i = 0; i < n / 2; i++)
		{
			addp(n - 1);
			for (int j = i, k = prv(i), c = 0; c < n / 2; c++, j = nxt(j), k = prv(k))
			{
				addp(j);
				addp(k);
			}
		}
		cout << n << "\n";
	}
	
	return 0;
}
// started coding at: 12-18 18:09:39