#include <bits/stdc++.h>
using namespace std;
bool comp(int x, int y) { return x > y; }
bool myComp(pair<int, int> x, pair<int, int> y) {
  if (x.first < y.first) return true;
  if (x.first > y.first) return false;
  return x.second > y.second;
}
int lucky[] = {4, 7, 44, 47, 74, 77, 444, 447, 474, 477, 744, 747, 774, 777};
int main() {
  int n, m;
  cin >> n >> m;
  int last = m - 1;
  for (int i = 0; i < n; i++) {
    bool print = false;
    for (int j = 0; j < m; j++) {
      if (i % 2 == 0)
        cout << '#';
      else {
        if (j != last) {
          cout << '.';
        } else {
          cout << '#';
        }
      }
    }
    if (i % 2 != 0) {
      if (last == 0)
        last = m - 1;
      else
        last = 0;
    }
    cout << endl;
  }
  return 0;
}
