#include <bits/stdc++.h>
using namespace std;
int main() {
  string a;
  cin >> a;
  int n = a.size();
  for (int i = 0; i < n; i++) {
    int x = a[i];
    if ((a[i] != 'a') && (a[i] != 'e') && (a[i] != 'i') && (a[i] != 'o') &&
        (a[i] != 'u') && (a[i] != 'A') && (a[i] != 'E') && (a[i] != 'I') &&
        (a[i] != 'y') && (a[i] != 'O') && (a[i] != 'U') && (a[i] != 'Y')) {
      if ((65 <= x) && (x <= 90)) {
        char z = a[i] + 32;
        cout << "." << z;
      } else if ((97 <= x) && (x <= 122)) {
        cout << "." << a[i];
      }
    }
  }
  return 0;
}
