#include <bits/stdc++.h>
using namespace std;
void printa(int y) {
  for (int i = 0; i < y; i++) cout << "#";
  cout << endl;
}
void printe(int y, int a) {
  if (a % 2 == 0) {
    for (int i = 1; i < y; i++) cout << ".";
    cout << "#" << endl;
  } else {
    cout << "#";
    for (int i = 1; i < y; i++) cout << ".";
    cout << endl;
  }
}
int main() {
  int x, y;
  cin >> x >> y;
  bool b = true;
  int c = 0;
  for (int i = 0; i < x; i++) {
    if (b) {
      printa(y);
      b = false;
    } else {
      printe(y, c);
      b = true;
      c++;
    }
  }
  return 0;
}
