#include <bits/stdc++.h>
using namespace std;
const long long mod = 1000000007;
void fastio() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
}
void solve() {
  int n, m;
  cin >> n >> m;
  char arr[n][m];
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      arr[i][j] = '.';
    }
  }
  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 += 4) {
    arr[i][m - 1] = '#';
  }
  for (int i = 3; i < n; i += 4) {
    arr[i][0] = '#';
  }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      cout << arr[i][j];
    }
    cout << '\n';
  }
}
int main() {
  fastio();
  int t = 1;
  while (t--) solve();
  return 0;
}
