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