#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(a, b) for(int a = 0; a < (b); ++a)
#define st first
#define nd second
#define pb push_back
#define all(a) a.begin(), a.end()
const int LIM=25e3+7;
int P[LIM], T[LIM], ile[LIM];
pair<int,int>mi[10];
void solve() {
	int n, k;
	cin >> n >> k;
	rep(i, n) P[i]=T[i]=0;
	rep(i, n-k+1) cin >> P[i];
	rep(i, n-k) T[k+i]=T[i]+P[i+1]-P[i];
	rep(i, k) mi[i]={0, i};
	rep(i, n) mi[i%k]=min(mi[i%k], {T[i], i});
	rep(i, n) T[i]-=mi[i%k].st;
	vector<int>V;
	vector<vector<int>>ans;
	rep(i, k) V.pb(i);
	do {
		vector<int>perm(n);
		rep(i, n) ile[i+1]=0;
		int l=1;
		bool ok=true;
		for(auto i : V) {
			while(ile[l]) ++l;
			for(int j=i; j<n; j+=k) {
				if(1<=l+T[j] && l+T[j]<=n) {
					++ile[l+T[j]];
					perm[j]=l+T[j];
				} else {
					ok=false;
					break;
				}
			}
			if(!ok) break;
		}
		if(!ok) continue;
		int ma=0;
		rep(i, n) ma=max(ma, ile[i+1]);
		if(ma!=1) continue;
		int sum=0;
		rep(i, k) sum+=perm[i];
		rep(i, n-k+1) {
			if(sum!=P[i]) ok=false;
			if(i+k<n) sum+=perm[i+k];
			sum-=perm[i];
		}
		if(ok) ans.pb(perm);
	} while(next_permutation(all(V)));
	sort(all(ans));
	cout << ans.size() << '\n';
	for(auto i : ans) {
		for(auto j : i) {
			cout << j << " ";
		}
		cout << '\n';
	}
}
int main() {
	ios_base::sync_with_stdio(0); cin.tie(0);
	int _=1;
	cin >> _;
	while(_--) solve();
}