#include <bits/stdc++.h>
using namespace std;
const int N = 1e6 + 7;
const int INF = 1e9 + 7;
const double EPS = 1e-12;
const int MOD = 1e9 + 7;
int fx[] = {1, -1, 0, 0, 1, 1, -1, -1};
int fy[] = {0, 0, 1, -1, -1, 1, -1, 1};
int n, m;
int main() {
  cin >> n >> m;
  for (int i = 1; i <= n; i++) {
    if (i % 2)
      for (int j = 0; j < m; j++) cout << "#";
    else {
      if (i % 4 == 0) cout << "#";
      for (int j = 1; j < m; j++) cout << ".";
      if (i % 4 != 0) cout << "#";
    }
    cout << endl;
  }
  return 0;
}
