#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 += "#";
    s2 += ".";
  }
  s2[m - 1] = '#';
  s3 = s2;
  int flag = 1;
  reverse(s3.begin(), s3.end());
  for (int i = 0; i < n; i++) {
    if (i % 2 == 0)
      cout << s1 << endl;
    else if (flag == 1) {
      cout << s2 << endl;
      flag = 0;
    } else {
      cout << s3 << endl;
      flag = 1;
    }
  }
  return 0;
}
