#include <bits/stdc++.h>
using namespace std;
int main() {
  string word;
  getline(cin, word);
  for (int i = 0; i < (int)word.size(); i++) {
    if (tolower(word[i]) == 'a' || tolower(word[i]) == 'o' ||
        tolower(word[i]) == 'y' || tolower(word[i]) == 'e' ||
        tolower(word[i]) == 'u' || tolower(word[i]) == 'i') {
      word.erase(i, 1);
      i--;
    } else {
      word[i] = tolower(word[i]);
      word.insert(i, ".");
      i++;
    }
  }
  cout << word << endl;
  return 0;
}
