#include <bits/stdc++.h>
using namespace std;
int main() {
  string data;
  cin >> data;
  transform(data.begin(), data.end(), data.begin(), ::tolower);
  vector<char> v(data.begin(), data.end());
  char ch;
  int i;
  for (i = 0; i < v.size(); i++) {
    ch = v[i];
    if (ch != 'a' && ch != 'e' && ch != 'o' && ch != 'u' && ch != 'i' &&
        ch != 'y')
      cout << "." << ch;
  }
  return 0;
}
