#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m;
  cin >> n >> m;
  int r = 1;
  bool l = false;
  while (r <= n) {
    if (r % 2 == 1) {
      for (int i = 0; i < m; i++) cout << "#";
      cout << endl;
    } else if (r % 2 == 0 && l == false) {
      for (int j = 0; j < m - 1; j++) cout << ".";
      cout << "#" << endl;
      l = true;
    } else {
      cout << "#";
      for (int j = 0; j < m - 1; j++) cout << ".";
      cout << endl;
      l = false;
    }
    r++;
  }
  return 0;
}
