#include <bits/stdc++.h>
int main() {
  int n = 0, m = 0;
  scanf("%d %d", &n, &m);
  int r = 1;
  int i = 0, j = 0;
  for (i = 0; i < n; i++) {
    if ((i + 1) % 4 == 0)
      r = 0;
    else if ((i + 1) % 4 == 2)
      r = 1;
    for (j = 0; j < m; j++) {
      if ((i + 1) % 2 == 1) {
        printf("#");
      } else {
        if (r == 0 && j == 0)
          printf("#");
        else if (r == 1 && j == m - 1)
          printf("#");
        else
          printf(".");
      }
    }
    printf("\n");
  }
}
