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