#include <bits/stdc++.h>
using namespace std;
int main() {
  string str, x = "aoyeui";
  cin >> str;
  for (int i = 0; i < str.length(); i++) {
    if (str[i] == 'e' || str[i] == 'E' || str[i] == 'a' || str[i] == 'A' ||
        str[i] == 'i' || str[i] == 'I' || str[i] == 'o' || str[i] == 'O' ||
        str[i] == 'u' || str[i] == 'U' || str[i] == 'y' || str[i] == 'Y')
      continue;
    else if (str[i] >= 'A' && str[i] <= 'Z')
      cout << "." << (char)(str[i] + 32);
    else
      cout << "." << str[i];
  }
  cout << endl;
  return 0;
}
