#include <bits/stdc++.h>
using namespace std;
char s[105], t[105], a[105];
int main() {
  int n, m, f = 0;
  scanf("%d%d", &n, &m);
  for (int i = 0; i < m; i++) {
    s[i] = '#';
    t[i] = '.';
    a[i] = '.';
  }
  t[m - 1] = '#';
  a[0] = '#';
  for (int i = 0; i < n; i++) {
    if (i % 2 == 0)
      cout << s << endl;
    else {
      if (f == 0) {
        cout << t << endl;
        f = 1;
      } else {
        cout << a << endl;
        f = 0;
      }
    }
  }
  return 0;
}
