#include <bits/stdc++.h>
using namespace std;
int main() {
  int i = 0;
  string s, res = "";
  getline(std::cin, s);
  for (int j = 0; j < s.length(); ++j) s[j] = tolower(s[j]);
  while (i != s.length()) {
    if (s[i] != 'a' && s[i] != 'o' && s[i] != 'y' && s[i] != 'e' &&
        s[i] != 'u' && s[i] != 'i') {
      res += '.';
      res += s[i];
    }
    ++i;
  }
  cout << res;
}
