#include <bits/stdc++.h>
using namespace std;
void solve();
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  solve();
}
void solve() {
  int n, m;
  cin >> n >> m;
  char arr[n][m];
  for (int i = 0; i < n; ++i)
    for (int j = 0; j < m; ++j) arr[i][j] = '.';
  for (int i = 0; i < n; ++i)
    for (int j = 0; j < m; ++j) {
      if (i % 2 == 0) {
        arr[i][j] = '#';
      }
    }
  int c = m - 1;
  for (int i = 0; i < n; ++i) {
    if (i % 2) {
      arr[i][c] = '#';
      if (c == 0) {
        c = m - 1;
      } else {
        c = 0;
      }
    }
  }
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < m; ++j) {
      cout << arr[i][j];
    }
    cout << '\n';
  }
}
