#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m;
  cin >> n >> m;
  int co = 1;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      if (i % 2)
        cout << "#";
      else {
        if (i % 4) {
          if (j == m)
            cout << "#";
          else
            cout << ".";
        } else {
          if (j == 1)
            cout << "#";
          else
            cout << ".";
        }
      }
    }
    cout << endl;
  }
}
