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#include <bits/stdc++.h>


using namespace std;

typedef long long LL;
typedef unsigned long long ULL;

const int MAXN = 3000 + 10;
const int INF = MAXN * MAXN;
const int MOD = 1e9 + 7;
int n, k;
string s[MAXN];

ULL w[MAXN][MAXN];
ULL curhash;

int dx[] = {0, 0, -1, 1};
int dy[] = {1, -1, 0, 0};

bool ins(int a, int b) {
    return a >= 0 && a < n && b >= 0 && b < n;
}

vector<pair<int,int>> cands;
int dist[MAXN][MAXN];
int used[MAXN][MAXN];
int iscnd[MAXN][MAXN];
int res;

unordered_set<LL> M;

void gogo(int x) {

    if (x == k) {

        if (M.insert(curhash).second) {
            res = (res + 1) % MOD;
        }

        return;
    }
    for (int i = 0; i < cands.size(); i++) {
        auto p = cands[i];

        if (used[p.first][p.second]) continue;

        used[p.first][p.second] = 1;
        curhash += w[p.first][p.second];
        int added = 0;
        for (int i = 0; i < 4; i++) {
            int x = p.first + dx[i];
            int y = p.second + dy[i];

            if (!ins(x, y)) continue;

            if (s[x][y] == '#') continue;

            if (iscnd[x][y]) continue;

            added++;

            iscnd[x][y] = 1;
            cands.push_back(make_pair(x, y));
        }
        gogo(x + 1);

        curhash -= w[p.first][p.second];
        for (int i = 0; i < added; i++) {
            auto p = cands.back();
            iscnd[p.first][p.second] = 0;
            cands.pop_back();
        }
        used[p.first][p.second] = 0;
    }
}

int main() {
    ios_base::sync_with_stdio(0);

    srand(time(0));

    cin >> n >> k;

    for (int i = 0; i < n; i++) {
        cin >> s[i];
    }

    queue<pair<int,int>> Q;

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {

            if (s[i][j] == '.') {
                w[i][j] = ((ULL)rand() << 32) + (unsigned)rand();
                dist[i][j] = INF;
            } else {
                Q.push(make_pair(i, j));
                dist[i][j] = 0;
            }

        }
    }

    while (!Q.empty()) {
        auto p = Q.front();

        Q.pop();

        if (dist[p.first][p.second] == k) {
            continue;
        }

        for (int i = 0; i < 4; i++) {
            int x = p.first + dx[i];
            int y = p.second + dy[i];

            if (!ins(x, y)) continue;

            if (dist[p.first][p.second] + 1 < dist[x][y]) {
                dist[x][y] = dist[p.first][p.second] + 1;
                Q.push(make_pair(x, y));
            }
        }
    }


    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (dist[i][j] == 1) {
                cands.push_back({i, j});
                iscnd[i][j] = 1;
            }
        }
    }

    gogo(0);

    cout << res << "\n";

    return 0;
}