#include <bits/stdc++.h>
using namespace std;
void solve() {
  int n, m, flag = 1;
  cin >> n >> m;
  for (int i = 0; i < n; i++) {
    int flag1 = 0;
    for (int j = 0; j < m; j++) {
      if (i % 2 == 0 && i != 1) {
        cout << "#";
      } else {
        if (flag == 1 && j == m - 1 && flag1 == 0) {
          cout << "#";
          flag = 0;
          flag1 = 1;
        } else if (flag == 0 && j == 0 && flag1 == 0) {
          cout << "#";
          flag = 1;
          flag1 = 1;
        } else {
          cout << ".";
        }
      }
    }
    cout << endl;
  }
  return;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int n = 1;
  while (n--) {
    solve();
  }
  return 0;
}
