#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m;
  cin >> n >> m;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      if (i % 2 == 1)
        cout << "#";
      else if (i % 4 == 2 && j == m)
        cout << "#";
      else if (i % 4 == 0 && j == 1)
        cout << "#";
      else
        cout << ".";
    }
    cout << endl;
  }
}
