#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m;
  cin >> n >> m;
  for (int i = 1; i <= n; i++) {
    if (i % 2 != 0)
      for (int i = 1; i <= m; i++) cout << "#";
    else if (i % 4 == 0) {
      cout << "#";
      for (int j = 1; j < m; j++) cout << ".";
    } else {
      for (int j = 1; j < m; j++) cout << ".";
      cout << "#";
    }
    cout << endl;
  }
  return 0;
}
