#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m;
  cin >> n >> m;
  string s[n];
  for (int i = 0; i < n; i++) {
    if (i % 2 == 0) {
      for (int j = 0; j < m; j++) s[i] += '#';
    } else if (((i + 1) / 2) % 2 != 0) {
      while (s[i].size() != m - 1) s[i] += '.';
      s[i] += '#';
    } else {
      s[i] += '#';
      while (s[i].size() != m) s[i] += '.';
    }
  }
  for (int i = 0; i < n; i++) cout << s[i] << endl;
}
