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