#define _CRT_SECURE_NO_WARNINGS 1
#include<bits/stdc++.h>
#include<unordered_map>
#include<unordered_set>
using namespace std;
#define ll long long
//#define double long double
#define lc u<<1
#define rc u<<1|1
#define X first
#define Y second
#define endl "\n"
#define int long long
const int N = 1e5 + 50;
const int M = 5e5 + 5;
const ll maxm = 1e18 + 5;
const ll mod = 998244353;
int dx[] = { -1,0,1,0 };
int dy[] = { 0,1,0,-1 };
//random_shuffle(id + 1, id + n + 1);
ll ksm(ll a, ll b);
ll gcd(ll a, ll b);

template<class T>inline void read(T& x) {
	x = 0;
	char c = getchar();
	while (!isdigit(c))c = getchar();
	while (isdigit(c))x = x * 10 + (c & 15), c = getchar();
}

void write(ll x)
{
	if (x < 0)
		putchar('-'), x = -x;
	if (x > 9)
		write(x / 10);
	putchar(x % 10 + '0');
	return;
}

ll mp[1005][1005];
int n, k;
int lowbit(int n) {
	return n & -n;
}

void solve() {
	cin >> n >> k;
	if (k > lowbit(n) - 1) {
		cout << "Impossible" << endl;
		return;
	}
	for (int j = 1; j <= n; j++) {
		/*
		if (j & 1)mp[1][j] = j + 1;
		else mp[1][j] = j - 1;*/
		mp[1][j] = j;
	}
	for (int j = 1; j <= n - 1; j += 2) {//枚举列
		if ((j + 1)/2 % 2 == 1) {
			ll st = 2;
			ll val = mp[1][j];
			for (int i = 0; i < n; i++) {
				val++; if (val == n + 1)val = 1;
				mp[st][j] = val;
				st++;
			}
		}
		else {
			ll st = n;
			j++;
			ll val = mp[1][j];
			for (int i = 0; i < n; i++) {
				val++; if (val == n+1)val = 1;
				mp[st][j] = val;
				st--;
			}
			j--;
		}
	}
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= n - 1; j += 2) {
			if ((j + 1) / 2 % 2 == 1) {
				ll st = j;
				if (mp[i][j] % 2 == 1)mp[i][j + 1] = mp[i][j] + 1;
				else mp[i][j + 1] = mp[i][j] - 1;
			}
			else {
				ll st = j;
				j++;
				if (mp[i][j] % 2 == 1)mp[i][j-1] = mp[i][j] + 1;
				else mp[i][j-1] = mp[i][j] - 1;
				j--;
			}
		}
	}
	for (int i = 2; i <= k + 1; i++) {
		cout << mp[i][1];
		for (int j = 2; j <= n; j++) {
			cout << " " << mp[i][j];
		}
		cout << endl;
	}

}


signed main()
{
	ios::sync_with_stdio(false);
	cin.tie(0), cout.tie(0);
	int T = 1;
	cin >> T;
	//read(T);
	while (T--)
		solve();
	return 0;
}

/*PonyHex*/


ll ksm(ll a, ll b) {
	ll base = a;
	ll ans = 1;
	while (b) {
		if (b & 1)ans *= base % mod;
		ans %= mod;
		base *= base; base %= mod;
		b >>= 1;
	}
	return ans % mod;
}
ll gcd(ll a, ll b) {
	return b ? gcd(b, a % b) : a;
}