#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  transform(s.begin(), s.end(), s.begin(), ::tolower);
  string s1 = "";
  for (int i = 0; i < s.length(); i++) {
    if (s[i] != 'a' && s[i] != 'e' && s[i] != 'i' && s[i] != 'o' &&
        s[i] != 'u' && s[i] != 'y') {
      s1 += s[i];
    }
  }
  string finalans = "";
  for (int i = 0; i < s1.length(); i++) {
    finalans.append(".");
    finalans += s1[i];
  }
  cout << finalans << "\n";
}
