#include <bits/stdc++.h>
using namespace std;
string s = "";
string s1 = "";
string s2 = "";
int main() {
  int n;
  int m;
  cin >> n >> m;
  int mp = m;
  int mp2 = m;
  int mp3 = m;
  s2 += '#';
  while (mp3 > 1) {
    s2 += '.';
    mp3--;
  }
  while (mp > 0) {
    s += '#';
    mp--;
  }
  while (mp2 > 1) {
    s1 += '.';
    mp2--;
  }
  s1 += '#';
  for (int i = 1; i <= n; i++) {
    if (i % 2 == 1) {
      cout << s << endl;
    }
    if (i % 4 == 2) {
      cout << s1 << endl;
    }
    if (i % 4 == 0) {
      cout << s2 << endl;
    }
  }
  return 0;
}
