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