#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  string b = "";
  for (int i = 0; i < s.length(); i++) {
    char temp = tolower(s[i]);
    if (temp == 'a' || temp == 'o' || temp == 'y' || temp == 'e' ||
        temp == 'u' || temp == 'i') {
    } else {
      char p = '.';
      b = b + p;
      b = b + temp;
    }
  }
  cout << b;
}
