#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  string s;
  cin >> s;
  int n = s.size();
  for (int i = 0; i < n; ++i) {
    s[i] = tolower(s[i]);
    if (s[i] == 'a' || s[i] == 'o' || s[i] == 'y' || s[i] == 'e' ||
        s[i] == 'u' || s[i] == 'i')
      continue;
    cout << '.' << s[i];
  }
}
