#include <bits/stdc++.h>
using namespace std;
int main() {
  int x, y;
  cin >> x >> y;
  for (int i = 1; i <= x; i++) {
    if (i % 2 == 1) {
      for (int j = 0; j < y; j++) {
        cout << "#";
      }
    } else {
      if ((i / 2) % 2 == 0) {
        cout << "#";
        for (int j = 0; j < y - 1; j++) {
          cout << ".";
        }
      } else {
        for (int j = 0; j < y - 1; j++) {
          cout << ".";
        }
        cout << "#";
      }
    }
    cout << "\n";
  }
  return 0;
}
