#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  long long t, n, k, m, f;
  cin >> n >> m;
  long long i = 1;
  f = 1;
  while (i <= n) {
    if (i & 1) {
      for (int j = 0; j < m; j++) {
        cout << "#";
      }
      cout << "\n";
    } else {
      if (f) {
        for (int j = 0; j < m - 1; j++) {
          cout << ".";
        }
        cout << "#";
        cout << "\n";
        f = 0;
      } else {
        cout << "#";
        for (int j = 0; j < m - 1; j++) {
          cout << ".";
        }
        cout << "\n";
        f = 1;
      }
    }
    i++;
  }
  return 0;
}
