#include <bits/stdc++.h>
using namespace std;
const int inf = 1 << 30;
const long long INF = 1ll << 60;
const double pi = acos(-1);
const double eps = 1e-9;
const long long mod = 1e9 + 7;
const int dx[4] = {0, 1, 0, -1}, dy[4] = {1, 0, -1, 0};
int n, m;
vector<string> a;
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cin >> n >> m;
  a = vector<string>(n);
  for (int i = 0; i < n; i++) {
    if (i % 2 == 0)
      a[i] = string(m, '#');
    else {
      a[i] = string(m, '.');
      if (i / 2 % 2 == 0)
        a[i][m - 1] = '#';
      else
        a[i][0] = '#';
    }
  }
  for (int i = 0; i < n; i++) cout << a[i] << endl;
}
