#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie();
  int n, m;
  cin >> n >> m;
  char arr[n][m];
  for (int i = 0; i < n; i += 2) {
    for (int j = 0; j < m; j++) arr[i][j] = '#';
  }
  for (int i = 1; i < n; i += 2) {
    for (int j = 0; j < m; j++) arr[i][j] = '.';
  }
  int l = m - 1;
  for (int i = 1; i < n; i += 2) {
    if (l == m - 1) {
      arr[i][l] = '#';
      l = 0;
    } else {
      arr[i][l] = '#';
      l = m - 1;
    }
  }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) cout << arr[i][j];
    cout << endl;
  }
  return 0;
}
