#include <bits/stdc++.h>
using namespace std;
int n, m, a[111][111];
int main() {
  cin >> n >> m;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) a[i][j] = 0;
  }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (i % 2 == 0 ||
          (i % 2 == 1 && ((j == 0 && (((i - 1) / 2) % 2 == 1)) ||
                          (j == m - 1 && (((i - 1) / 2) % 2 == 0)))))
        a[i][j] = 1;
    }
  }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (a[i][j] == 1) {
        cout << "#";
      } else
        cout << ".";
    }
    cout << endl;
  }
  return 0;
}
