#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, k;
  cin >> n >> k;
  bool check = true;
  for (int x = 0; x < n; x++) {
    int z = (check) ? k - 1 : 0;
    for (int y = 0; y < k; y++) {
      if (x % 2 == 0)
        cout << "#";
      else {
        if (y == z) {
          cout << "#";
          check = !check;
        } else
          cout << ".";
      }
    }
    cout << endl;
  }
  return 0;
}
