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