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