#include <bits/stdc++.h>
using namespace std;
int main() {
  string str, str1;
  cin >> str;
  int x = str.length();
  for (int i = 0; i < x; i++) {
    if (str[i] == 'a' || str[i] == 'e' || str[i] == 'i' || str[i] == 'o' ||
        str[i] == 'u' || str[i] == 'y' || str[i] == 'A' || str[i] == 'E' ||
        str[i] == 'I' || str[i] == 'O' || str[i] == 'U' || str[i] == 'Y')
      continue;
    else
      str1 += '.';
    str1 += towlower(str[i]);
  }
  cout << str1 << endl;
  return 0;
}
