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