#include <bits/stdc++.h>
int main() {
  int n, m;
  scanf("%d %d", &n, &m);
  int last = 0;
  for (int i = 1; i <= n; i++) {
    if (i & 1) {
      for (int i = 1; i <= m; i++) putchar('#');
      putchar('\n');
    } else if (last) {
      last ^= 1;
      putchar('#');
      for (int i = 1; i < m; i++) putchar('.');
      putchar('\n');
    } else {
      last ^= 1;
      for (int i = 1; i < m; i++) putchar('.');
      putchar('#');
      putchar('\n');
    }
  }
  return 0;
}
