#include <bits/stdc++.h>
using namespace std;
int main() {
  string s, s2;
  cin >> s;
  int x = s.length();
  for (int i = 0; i < x; i++) {
    if (s[i] == 'a' || s[i] == 'e' || s[i] == 'i' || s[i] == 'o' ||
        s[i] == 'u' || s[i] == 'y' || s[i] == 'A' || s[i] == 'E' ||
        s[i] == 'I' || s[i] == 'O' || s[i] == 'U' || s[i] == 'Y') {
      continue;
    } else {
      s2 += '.';
      s2 += towlower(s[i]);
    }
  }
  cout << s2 << endl;
}
