#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, m;
  cin >> n >> m;
  bool left = false;
  for (int i = 0; i < (int)n; ++i) {
    if (i % 2 != 0) {
      string temp(m - 1, '.');
      if (left) {
        cout << "#" << temp << "\n";
        left = false;
      } else {
        cout << temp << "#"
             << "\n";
        left = true;
      }
      continue;
    }
    for (int j = 0; j < (int)m; ++j) cout << "#";
    cout << "\n";
  }
  return 0;
}
