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