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