#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, k = 1, l = 1;
  cin >> n >> m;
  for (int i = 0; i < n; i++) {
    if (i % 2 == 0) {
      for (int j = 0; j < m; j++) {
        cout << "#";
      }
    } else if (i == 4 * k - 3) {
      for (int j = 0; j < m - 1; j++) {
        cout << ".";
      }
      cout << "#";
      k++;
    } else if (i == 4 * l - 1) {
      cout << "#";
      for (int j = 1; j < m; j++) {
        cout << ".";
      }
      l++;
    }
    cout << "\n";
  }
  return 0;
}
