#include <bits/stdc++.h>
using namespace std;
int main() {
  string a;
  cin >> a;
  for (int i = 0; i < a.length(); i++) {
    if (isupper(a[i])) a[i] = tolower(a[i]);
  }
  string s = " ";
  for (int i = 0; i < a.length(); i++) {
    if (a[i] == 'a' || a[i] == 'o' || a[i] == 'u' || a[i] == 'e' ||
        a[i] == 'i' || a[i] == 'y')
      continue;
    s += ".";
    s += a[i];
  }
  cout << s;
  return 0;
}
