#include <bits/stdc++.h>
using namespace std;
bool check_glas(char c) {
  if (c == 'A' || c == 'O' || c == 'Y' || c == 'E' || c == 'U' || c == 'I') {
    return true;
  }
  if (c == 'a' || c == 'o' || c == 'y' || c == 'e' || c == 'u' || c == 'i') {
    return true;
  }
  return false;
}
int main() {
  string data, result;
  cin >> data;
  for (char c : data) {
    if (!check_glas(c)) {
      result += '.';
      result += tolower(c);
    }
  }
  cout << result;
  return 0;
}
