#include <bits/stdc++.h>
using namespace std;
inline void INPUT(const string &s) { freopen((s).c_str(), "r", stdin); }
inline void OUTPUT(const string &s) { freopen((s).c_str(), "w", stdout); }
string str;
int main() {
  cin >> str;
  for (int i = 0; i < str.size(); ++i) {
    if (str[i] >= 'A' && str[i] <= 'Z') {
      str[i] = (str[i] - 'A') + 'a';
    }
  }
  for (int i = 0; i < str.size(); ++i) {
    if (str[i] == 'a' || str[i] == 'i' || str[i] == 'u' || str[i] == 'e' ||
        str[i] == 'o' || str[i] == 'y') {
    } else {
      printf(".");
      printf("%c", str[i]);
    }
  }
  return 0;
}
