#include <bits/stdc++.h>
bool isVowel(const char &c) {
  switch (c) {
    case 'a':
    case 'e':
    case 'i':
    case 'o':
    case 'u':
    case 'y':
      return true;
    default:
      return false;
  }
}
int main() {
  std::string word;
  std::cin >> word;
  for (auto &c : word) {
    c = std::tolower(c);
    if (!isVowel(c)) {
      std::cout << '.' << c;
    }
  }
  std::cout << std::endl;
  return 0;
}
