#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int n, m;
  cin >> n >> m;
  char a[n][m];
  long long int flag = 0;
  for (long long int i = 0; i < n; i++) {
    for (long long int j = 0; j < m; j++) {
      if (i % 2 != 0) {
        if (((i + 1) / 2) % 2 != 0) {
          if (j == m - 1)
            cout << "#";
          else
            cout << ".";
        } else {
          if (j == 0)
            cout << "#";
          else
            cout << ".";
        }
      } else {
        cout << '#';
      }
    }
    cout << '\n';
  }
  return 0;
}
