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