#include <bits/stdc++.h>

using namespace std;

#define FOR(i, a, b) for(int i = (a); i < (b); i++)
#define RFOR(i, a, b) for(int i = (a) - 1; i >= (b); i--)
#define SZ(a) int(a.size())
#define ALL(a) a.begin(), a.end()
#define PB push_back
#define MP make_pair
#define F first
#define S second

typedef long long LL;
typedef vector<int> VI;
typedef pair<int, int> PII;
typedef double db;

bool check(int n, int k, VI& p, VI& a)
{
	int s = 0;
	FOR (i, 0, k)
		s += a[i];
	if (s != p[0])
		return 0;
	FOR (i, k, n)
	{
		s += a[k];
		s -= a[i - k];
		if (s != p[i - k + 1])
			return 0;
	}
	return 1;
}

void solve()
{
	int n, k;
	cin >> n >> k;
	VI a(n - k + 1);
	FOR (i, 0, n - k + 1)
		cin >> a[i];
	VI mnK(k);
	VI d(k);
	FOR (i, 0, n - k + 1 - k)
	{
		d[k] += a[i + k] - a[i];
		mnK[k] = min(mnK[k], d[k]);
	}
	VI p(k);
	iota(ALL(p), 0);
	vector<VI> ans;
	do
	{
		VI cnt(n);
		VI b(n);
		bool ok = true;
		FOR (j, 0, k)
		{
			int mn = -1;
			FOR (i, 0, n)
			{
				if (cnt[i] == 0)
				{
					mn = i;
					break;
				}
			}
			int i = p[j];
			int el = mn - mnK[j];
			
			while (i < n)
			{
				b[i] = el;
				if (cnt[el])
				{
					ok = false;
					break;
				}
				cnt[el]++;
				int i2 = i + k;
				if (i2 < SZ(a))
				{
					el += a[i2];
					el -= a[i];
				}
				i = i2;
			} 
			if (!ok)
				break;
		}
		if (!ok)
			continue;	
		if (check(n, k, a, b))
			ans.PB(b);
		
	} while (next_permutation(ALL(p)));
	
	cout << SZ(ans) << '\n';
	for (auto v : ans)
	{
		FOR (i, 0, n)
		{
			if (i)
				cout << ' ';
			cout << v[i];
		}
		cout << '\n';
	}
}

int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	int t;
	cin >> t;
	while (t--)
		solve();
	
	return 0;
}