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