#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(false);
  int c, r;
  cin >> c >> r;
  bool flag = true;
  for (int i = 1; i <= c; i++) {
    if (i & 1) {
      for (int j = 1; j <= r; j++) {
        cout << "#";
      }
      cout << endl;
    } else {
      if (flag) {
        for (int j = 1; j <= r - 1; j++) {
          cout << ".";
        }
        cout << "#" << endl;
        flag = false;
      } else {
        cout << "#";
        for (int j = 1; j <= r - 1; j++) {
          cout << ".";
        }
        cout << endl;
        flag = true;
      }
    }
  }
  return 0;
}
