#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, i, j;
  cin >> n >> m;
  for (i = 1; i <= n; i++) {
    for (j = 0; j < m; j++) {
      if (i % 4 == 0) {
        if (j == 0)
          cout << "#";
        else
          cout << ".";
      } else if (i % 4 == 2) {
        if (j == m - 1)
          cout << "#";
        else
          cout << ".";
      } else
        cout << "#";
    }
    cout << endl;
  }
}
