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#include <cstdio>
#include <queue>
#include <map>
#include <algorithm>
#include <vector>
using namespace std;

const int N = 100;
const int dx[] = {1, 0, -1, 0}, dy[] = {0, 1, 0, -1};
bool board[N + 1][N + 1];
map<vector<pair<int, int> >, bool> M;
int n, k, result;
pair<int, int> start;

void read() {
    scanf("%d%d", &n, &k);
    for(int i = 0; i < n; ++i) {
        getchar();
        for(int j = 0; j < n; ++j) {
            char a;
            scanf("%c", &a);
            if(a == '#') {
                board[i][j] = true;
                start = make_pair(i, j);
            }
        }
    }
}

void go(int howMany, vector<pair<int, int> > V) {
    sort(V.begin(), V.end());
    if(M.find(V) != M.end()) {
        return;
    }
    M[V] = true;

    if(howMany == k) {
        ++result;
        return;
    }

    bool odw[N + 1][N + 1];
    for(int i = 0; i < n; ++i) {
        for(int j = 0; j < n; ++j) {
            odw[i][j] = false;
        }
    }

    queue<pair<int, int> > Q;
    vector<pair<int, int> > temp;
    odw[start.first][start.second] = true;
    Q.push(start);
    while(!Q.empty()) {
        pair<int, int> v = Q.front();
        Q.pop();

        for(int i = 0; i < 4; ++i) {
            int nx = v.first + dx[i], ny = v.second + dy[i];
            if(nx == -1 or nx == n or ny == -1 or ny == n or odw[nx][ny])
                continue;

            if(!board[nx][ny]) {
                board[nx][ny] = true;
                temp = V;
                temp.push_back(make_pair(nx, ny));
                go(howMany + 1, temp);
                board[nx][ny] = false;
            }
            else
                Q.push(make_pair(nx, ny));
            odw[nx][ny] = true;
        }
    }
}

int main()
{
    read();
    vector<pair<int, int> > V;
    go(0, V);
    printf("%d", result);
    return 0;
}