#include <bits/stdc++.h>
using namespace std;
int main() {
  long long n, m, c = 1;
  cin >> n >> m;
  char arr[n][m];
  for (long long i = 0; i < n; i++) {
    bool found = true;
    for (long long j = 0; j < m; j++) {
      if (i % 2 == 0) {
        arr[i][j] = '#';
        found = false;
      } else {
        if ((j == m - 1 && c % 2 != 0) || (j == 0 && c % 2 == 0)) {
          arr[i][j] = '#';
        } else {
          arr[i][j] = '.';
        }
      }
    }
    if (found) {
      c++;
    }
  }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      cout << arr[i][j];
    }
    cout << endl;
  }
  return 0;
}
