#include <bits/stdc++.h>
using namespace std;
int main() {
  char s1;
  while (cin >> s1) {
    s1 = tolower(s1);
    if (!(s1 == 'a' || s1 == 'o' || s1 == 'y' || s1 == 'i' || s1 == 'u' ||
          s1 == 'e'))
      cout << "." << s1;
  }
}
