#include <bits/stdc++.h>
int main() {
  int n, m, counter = 1;
  scanf("%i%i", &n, &m);
  for (int i = 1; i <= n; i++) {
    if (i % 2 != 0) {
      for (int j = 0; j < m; j++) {
        printf("#");
      }
      printf("\n");
    } else {
      if (counter % 2 != 0) {
        for (int j = 1; j < m; j++) {
          printf(".");
        }
        printf("#");
        printf("\n");
      } else {
        printf("#");
        for (int j = 1; j < m; j++) {
          printf(".");
        }
        printf("\n");
      }
      counter++;
    }
  }
  return 0;
}
