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#include <iostream>
#include <algorithm>
#include <unordered_set>
#include <set>

using namespace std;
typedef long long ll;

const int MAX_N = 1001;

vector<pair<ll,ll>> moves = {{1,0},{-1,0},{0,1},{0,-1}};

class Solution{

public:
    bool board[MAX_N][MAX_N];
    int boardSize;
    int enemiesCount;
    ll answer;
    vector<pair<ll,ll>> currentSetup;
    set<pair<int,int>> visited;


    Solution(int boardSize, int enemiesCount) : boardSize(boardSize), enemiesCount(enemiesCount){
        answer = 0;

    };

    void loadBoard(){
        char tile;

        for(int y=0; y< boardSize; ++y){
            for(int x=0; x< boardSize; ++x){
                cin >> tile;
                board[y][x] = (tile == '#');
            }
        }
    }

    bool fieldIsCurrent(ll y, ll x){
        for(auto field : currentSetup){
            if(field.first == y && field.second == x){
                return true;
            }
        }

        return false;
    }

    bool checkField(int y, int x){
        //cout << "checking field " << endl;
        visited.emplace(y,x);
        if(!fieldIsCurrent(y,x)){
            return true;
        }

        for(auto move : moves){

            ll tmpY, tmpX;
            tmpY = y + move.first;
            tmpX = x + move.second;

            if(tmpY <0 || tmpY >= boardSize || tmpX < 0 || tmpX >=boardSize){
                continue;
            }


            if(board[tmpY][tmpX] && visited.find(make_pair(tmpY, tmpX)) == visited.end()){
                if(checkField(tmpY, tmpX)){
                    return true;
                }
            }

        }
//        cout << x << " " << y << endl;
        return false;
    }

    void checkSetup(){


        for(auto field : currentSetup){
            visited.clear();
            //cout << field.first << " " << field.second << endl;
            if(!checkField(field.first, field.second)){
                return;
            }

        }

        answer = (answer +1) % ((ll) 1e9 +7);
    }

    ll getAnswer(){
        int k = enemiesCount;
        for(int y=0; y < boardSize; ++y){
            for(int x=0; x < boardSize; ++x){
                if(!board[y][x]){
                    board[y][x] = true;
                    currentSetup.emplace_back(y,x);
                    getAnswerHelper(k-1,y,x+1);
                    currentSetup.pop_back();
                    board[y][x] = false;
                }
            }
        }

        return answer;
    }

    void getAnswerHelper(int k, int y, int x){
       // cout << "k: " << k << " y: " << y << " x: " << x << endl;

        if(k==0){
            checkSetup();
            return;
        }

        if(x==boardSize){
            x=0;
            y++;
            if(y == boardSize){
                return;
            }
        }

        for(int y_2 = y;y_2 < boardSize; ++y_2){
            for(int x_2=0; x_2 < boardSize; ++x_2){
                if(y_2 == y && x_2 < x){
                    continue;
                }

                if(!board[y_2][x_2]){
                    board[y_2][x_2] = true;
                    currentSetup.emplace_back(y_2,x_2);
                    getAnswerHelper(k-1,y_2,x_2+1);
                    currentSetup.pop_back();
                    board[y_2][x_2] = false;
                }
            }
        }
    }

};

int main() {

    int n, k;
    cin >> n >> k;

    Solution solution(n, k);
    solution.loadBoard();

    cout << solution.getAnswer() << "\n";

    return 0;
}