#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m;
  cin >> n >> m;
  string sOdd = "";
  string sEven1 = "";
  string sEven2 = "";
  for (int i = 0; i < m; i++) {
    sOdd += '#';
  }
  for (int i = 0; i < m - 1; i++) {
    sEven1 += '.';
  }
  sEven1 += '#';
  sEven2 += '#';
  for (int i = 1; i < m; i++) {
    sEven2 += '.';
  }
  int even = 0;
  for (int i = 1; i <= n; i++) {
    if (i % 2 != 0) {
      cout << sOdd << endl;
    } else if (even == 0) {
      cout << sEven1 << endl;
      even = 1;
    } else {
      cout << sEven2 << endl;
      even = 0;
    }
  }
}
