#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b;
  cin >> a >> b;
  int x = 1;
  for (int i = 0; i < a; i++) {
    if (i % 2 == 0) {
      for (int j = 0; j < b; j++) {
        cout << "#";
      }
      cout << '\n';
    } else {
      if (x == 1) {
        for (int j = 0; j < (b - 1); j++) {
          cout << ".";
        }
        cout << "#" << endl;
        x = 2;
      } else if (x == 2) {
        cout << "#";
        for (int j = 1; j < (b); j++) {
          cout << ".";
        }
        cout << endl;
        x = 1;
      }
    }
  }
}
