#include <bits/stdc++.h>
using namespace std;
string a;
int main() {
  cin >> a;
  for (int i = 0; i < a.size(); i++) {
    if (a[i] >= 'A' && a[i] <= 'Z') a[i] += 32;
    if (a[i] != 'a' && a[i] != 'o' && a[i] != 'y' && a[i] != 'e' &&
        a[i] != 'u' && a[i] != 'i')
      cout << "." << a[i];
  }
  return 0;
}
