#include <bits/stdc++.h>
using namespace std;
class TaskA {
 public:
  void solve(istream& in, ostream& out) {
    int n, m;
    in >> n >> m;
    int cell = m - 1;
    for (int i = 0; i < n; ++i) {
      if (i & 1) {
        for (int j = 0; j < m; ++j) out << (j == cell ? '#' : '.');
        cell = (cell == m - 1 ? 0 : m - 1);
      } else
        for (int j = 0; j < m; ++j) out << '#';
      out << '\n';
    }
  }
};
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  TaskA solver;
  std::istream& in(std::cin);
  std::ostream& out(std::cout);
  solver.solve(in, out);
  return 0;
}
