#include <bits/stdc++.h>
using namespace std;
int main() {
  string str;
  cin >> str;
  for (int i = 0; str[i] != '\0'; i++) {
    if (str[i] >= 65 && str[i] <= 90) str[i] = str[i] + 32;
  }
  for (int i = 0; str[i] != '\0'; i++) {
    if (str[i] == 'a' || str[i] == 'e' || str[i] == 'i' || str[i] == 'o' ||
        str[i] == 'u' || str[i] == 'y')
      cout << "";
    else
      cout << '.' << str[i];
  }
}
