#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m;
  cin >> n >> m;
  string s1, s2, s3;
  for (int i = 0; i < m; i++) s1 += "#";
  for (int i = 1; i < m; i++) s2 += ".";
  s2 += "#";
  s3 += "#";
  for (int i = 1; i < m; i++) s3 += ".";
  bool check = true;
  for (int i = 0; i < n; i++) {
    if (i % 2 == 0)
      cout << s1 << '\n';
    else if (check)
      cout << s2 << '\n', check = false;
    else
      cout << s3 << '\n', check = true;
  }
  return 0;
}
