#include <bits/stdc++.h>
int main() {
  int n, m;
  scanf("%d%d", &n, &m);
  char a[n][m];
  for (int i = 0; i < n; i += 2) {
    for (int j = 0; j < m; j++) {
      a[i][j] = '#';
    }
  }
  for (int i = 1; i < n; i += 4) {
    for (int j = 0; j < m - 1; j++) {
      a[i][j] = '.';
    }
    a[i][m - 1] = '#';
  }
  for (int i = 3; i < n; i += 4) {
    a[i][0] = '#';
    for (int j = 1; j < m; j++) {
      a[i][j] = '.';
    }
  }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      printf("%c", a[i][j]);
    }
    printf("\n");
  }
  return 0;
}
