#include <bits/stdc++.h>
using namespace std;
long long mod = 1e+9 + 7;
void solve() {
  long long m, n, e = 0;
  cin >> n >> m;
  for (long long i = 1; i <= n; i++) {
    if (i % 2 != 0) {
      for (long long j = 1; j <= m; j++) cout << "#";
      cout << "\n";
    } else if (i % 2 == 0 && e == 0) {
      for (long long j = 1; j < m; j++) cout << ".";
      cout << "#"
           << "\n";
      e = 1;
    } else if (i % 2 == 0 && e == 1) {
      cout << "#";
      for (long long j = 1; j < m; j++) cout << ".";
      e = 0;
      cout << "\n";
    }
  }
}
int32_t main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  solve();
  return 0;
}
