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#include <algorithm>
#include <cstdio>
#include <cstring>
#include <set>
#include <utility>
#include <vector>

std::vector<std::pair<int, int>> operator+(std::vector<std::pair<int, int>> a, const std::vector<std::pair<int, int>> &b) {
  for (auto it : b) 
    a.push_back(it);
  return a;
}

const int MX = 3007;

char S[MX][MX];
int n, k;

bool ins(int x, int y) {
  return (1 <= x && x <= n && 1 <= y && y <= n);
}

std::set<std::vector<std::pair<int, int>>> bartosz_kostka;

bool ok(int x, int y) {
  static const int dx[] = {-1, 1, 0, 0};
  static const int dy[] = {0, 0, 1, -1};

  if (ins(x, y) == false || S[x][y] == '#')
    return false;

  for (int i = 0; i < 4; ++i) {
    if (ins(x + dx[i], y + dy[i]) && S[x + dx[i]][y + dy[i]] == '#')
      return true;
  }

  return false;
}

void rek(int d, std::vector<std::pair<int, int>> vec) {
  if (d == k) {
    std::sort(vec.begin(), vec.end());
    bartosz_kostka.insert(vec);
    return;
  }

  for (int i = 1; i <= n; ++i) {
    for (int j = 1; j <= n; ++j) {
      if (ok(i, j)) {
        S[i][j] = '#';
        vec.emplace_back(i, j);
        rek(d + 1, vec);
        vec.pop_back();
        S[i][j] = '.';
      }
    }
  }

  
  return;
}



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

  for (int i = 1; i <= n; ++i) {
    scanf(" %s", S[i] + 1);
  }

  rek(0, {});

  printf("%lu\n", bartosz_kostka.size());

  return 0;

  for (auto it : bartosz_kostka) {
    for (auto ptr : it) {
      printf("{%d, %d} ", ptr.first, ptr.second);
    }
    puts("");
  }

  return 0;
}