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#include <bits/stdc++.h>

using namespace std;

const int mod = 1e9+7;

char in[3005][3005];
bool active[3005][3005];
bool locked[5][3005][3005];
int res = 0;

void go(int n, int k)
{
    if(k == 0)
    {
        ++res;
        res %= mod;
        return;
    }
    for(int i = 1;i <= n;++i)
    {
        for(int j = 1;j <= n;++j)
        {
            if(!locked[k][i][j] && in[i][j] == '.' && active[i][j])
            {
                //cout << k << i << j << endl;
                for(int x = k-1;x >= 0;--x)
                    locked[x][i][j] = true;
                bool b1 = active[i-1][j];
                bool b2 = active[i+1][j];
                bool b3 = active[i][j-1];
                bool b4 = active[i][j+1];
                active[i][j-1] = active[i][j+1] = active[i-1][j] = active[i+1][j] = true;
                go(n, k-1);
                active[i-1][j] = b1;
                active[i+1][j] = b2;
                active[i][j-1] = b3;
                active[i][j+1] = b4;
            }
        }
    }
}


int main()
{
    int n, k;
    scanf("%d%d", &n, &k);

    for(int i = 1;i <= n;++i)
    {
        for(int j = 1;j <= n;++j)
        {
            scanf(" %c", &in[i][j]);
        }
    }
    for(int i = 1;i <= n;++i)
    {
        for(int j = 1;j <= n;++j)
        {
            if(in[i][j] == '.' && (in[i][j-1] == '#' || in[i][j+1] == '#' || in[i-1][j] == '#' || in[i+1][j] == '#'))
            {
                active[i][j] = true;
            }
        }
    }
    go(n, k);

    printf("%d\n", res);

    return 0;
}