#include <bits/stdc++.h>
using namespace std;
bool swi = false;
bool ok;
int main() {
  ios::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 % 2 != 0)
        cout << "#";
      else {
        if (swi == false) {
          if (j == m) {
            cout << "#";
            ok = true;
          } else
            cout << ".";
        } else {
          if (j == 1) {
            cout << "#";
            ok = false;
          } else
            cout << ".";
        }
      }
    }
    swi = ok;
    cout << "\n";
  }
  return 0;
}
