#include <bits/stdc++.h>
using namespace std;
bool isvowel(char c) {
  if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' || c == 'y' ||
      c == 'A' || c == 'O' || c == 'E' || c == 'I' || c == 'U' || c == 'Y')
    return true;
  return false;
}
int main() {
  string s;
  cin >> s;
  for (int i = 0; i < s.size();) {
    if (isvowel(s[i]))
      s.erase(s.begin() + i);
    else {
      int x = s[i];
      if (isupper(x)) s[i] = tolower(x);
      s.insert(s.begin() + i, '.');
      i = i + 2;
    }
  }
  cout << s << "\n";
  return 0;
}
