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#include <bits/stdc++.h>
#include <unordered_set>
#define ll long long int
#define UI unsigned int
#define duzo  30000000
#define inf 0xfffffff
using namespace std;

unordered_set<bitset<32*4> > Wyn;

//vector<vector<bool> > 
int n, k;
inline void AddWyn(vector<UI> ToAdd) {
	sort(ToAdd.begin(), ToAdd.end());
	for (int i = k; i < 4; i++)
	{
		ToAdd.push_back(inf);
	}
	ll p1 = (((ll)ToAdd[0]) << 32) +(ll) ToAdd[1];
	ll p2 = (((ll)ToAdd[2])<<32) + (ll)ToAdd[3];
	bitset<32 * 4> bs1(p1);
	bitset<32 * 4> bs2(p2);
	bs1 = bs1<<64;
	bs1 |= bs2;
	Wyn.insert(bs1);
}



inline UI Flaten2d(UI a,UI b) {
	return (a << 16) + b;
}

struct Graf
{

	vector <vector<bool> > Data;
	vector<UI> cur;
	template<typename T>
	bool VisitFriends(int x,int y,T Run) {
		// n <-- max size
		const static vector<int> rotx = { 1,0,-1,0 };
		const static vector<int> roty = { 0,1,0,-1 };
		bool out = false;
		for (int i = 0; i < 4; i++)
		{
			if (x + rotx[i] >= 0 && x + rotx[i] < n && (y + roty[i]) >= 0 && y + roty[i] < n) {
				out|= Run(x + rotx[i], y + roty[i]);
			}
		}
		return out;
	}


	void VisitEveryone() {
		
		auto Check = [&](int a, int b) {
			if (!Data[a][b])
			{
				vector<UI> tmp = cur;
				tmp.push_back(Flaten2d(a, b));
				AddWyn(tmp);
			}
			return 0;
		};

		for (int i = 0; i < n; i++)
		{
			for (int j = 0; j < n; j++)
			{
				if (Data[i][j])
				{
					VisitFriends(i, j, Check);
				}
			}
		}
	}
	
};

void IterateOver(int MaxDepth,Graf G,vector<UI> nums) {
	if (MaxDepth == 1)
	{
		G.VisitEveryone();
		return;
	}
	auto QCheck = [&](int x, int y) {
		return G.Data[x][y];
	};
	

	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < n; j++)
		{
			if (G.Data[i][j] || !G.VisitFriends(i,j,QCheck))
			{
				continue;
			}
			auto tmp = G;
			tmp.Data[i][j] = true;
			tmp.cur.push_back(Flaten2d(i, j));
			IterateOver(MaxDepth-1, tmp,nums);
		}
	}

}


int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	Wyn.reserve(duzo);

	cin >> n >> k;
	Graf G;
	G.Data.resize(n, vector<bool>(n));
	for (int i = 0; i < n; i++)
	{
		string s;
		cin >> s;
		for (int j = 0; j < n; j++)
		{
			G.Data[i][j] = (s[j] == '#');
		}
	}
	vector<UI> ppp;
	IterateOver(k, G,ppp);
	cout << Wyn.size();
	return 0;
}