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