#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int t = 1;
  while (t--) {
    string s;
    cin >> s;
    transform(s.begin(), s.end(), s.begin(), ::tolower);
    for (int i = 0; i < s.size(); i++) {
      if (s[i] != 'a' && s[i] != 'e' && s[i] != 'i' && s[i] != 'o' &&
          s[i] != 'u' && s[i] != 'y')
        cout << '.' << s[i];
    }
    cout << "\n";
  }
  return 0;
}
