#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 / 2) % 2 == 0) {
          if (j == 1) {
            cout << "#";
          } else {
            cout << ".";
          }
        } else {
          if (j == m) {
            cout << "#";
          } else {
            cout << ".";
          }
        }
      }
    }
    cout << endl;
  }
}
