#include <bits/stdc++.h>
using namespace std;
string n;
int main() {
  cin >> n;
  for (int i = 0; i < n.size(); i++) {
    if (n[i] <= 'Z') n[i] = char(n[i] - 'A' + 'a');
    if (n[i] != 'a' && n[i] != 'e' && n[i] != 'i' && n[i] != 'o' &&
        n[i] != 'u' && n[i] != 'y')
      cout << "." << n[i];
  }
  cout << endl;
  return 0;
}
