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