#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  ;
  int n, m;
  cin >> n >> m;
  for (int i = 1; i <= n; ++i) {
    for (int j = 1; j <= m; ++j) {
      if (i & 1)
        cout << '#';
      else {
        int num = i / 2;
        if (num & 1) {
          if (j == m)
            cout << '#';
          else
            cout << '.';
        } else {
          if (j == 1)
            cout << '#';
          else
            cout << '.';
        }
      }
    }
    cout << '\n';
  }
  return 0;
}
