#include <bits/stdc++.h>
using namespace std;
int MAIN() {
  int n, m;
  cin >> n >> m;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      bool haveSnake = false;
      if (i % 2 == 1)
        haveSnake = true;
      else {
        if (i % 4 == 2) haveSnake = (j == m);
        if (i % 4 == 0) haveSnake = (j == 1);
      }
      cout << (haveSnake ? "#" : ".");
    }
    cout << endl;
  }
  return 0;
}
int main() {
  ios ::sync_with_stdio(false);
  cout << fixed << setprecision(16);
  return MAIN();
}
