#include <bits/stdc++.h>
using namespace std;
int main(int argc, char** argv) {
  int a, b;
  cin >> a >> b;
  bool cmd = true;
  for (int i = 0; i < b; i++) cout << "#";
  cout << endl;
  for (int i = 1; i < a; i += 2) {
    if (cmd) {
      for (int i = 1; i < b; i++) cout << ".";
      cout << '#' << endl;
    }
    if (!cmd) {
      cout << '#';
      for (int i = 1; i < b; i++) cout << ".";
      cout << endl;
    }
    cmd = !cmd;
    for (int i = 0; i < b; i++) cout << "#";
    cout << endl;
  }
  return 0;
}
