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