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#include <iostream>
#include <cmath>
#include <vector>

using namespace std;
#define mod 1000000007

void possib(vector<bool> board, unsigned k, int n, unsigned it, unsigned &p);
vector<vector<bool>> past;

int main(){
    cin.tie(NULL);
    ios::sync_with_stdio(false);
    unsigned n,k;
    cin >> n >> k;

    unsigned n2 = n*n;
    vector<bool> board(n2,0);
    for(unsigned i = 0; i < n2; ++i){
        char c;
        cin >> c;
        if(c == '#')
            board[i] = 1;
        else
            board[i] = 0;
    }
    unsigned pos=0;
    possib(board, k, n, 0, pos);
    cout << pos%mod << endl;

    return 0;
}

void possib(vector<bool> board, unsigned k, int n, unsigned it, unsigned &p){
    if(k == 0){
        for(unsigned i=0; i<past.size(); ++i){
            if(past[i]==board)
                return;
        }
        past.push_back(board);
        ++p;
        if(p >= mod)
            p%=mod;
        return;
    }
    int en = board.size();
    for(int i=it; i<en; ++i){
        if(board[i] == 0 && ((i%n>0 && board[i-1]) || ((i+1)%n > 0 && board[i+1]) || (i>=n && board[i-n]) || (i<n*(n-1) && board[i+n]))){
            board[i] = 1;
            possib(board, k-1, n, max(0,i-n), p);
            board[i] = 0;
        }
    }
}