#include <bits/stdc++.h>
using namespace std;
int main() {
  string a, ans;
  cin >> a;
  int len = a.length();
  for (int i = 0; i < len; i++) {
    if (a[i] == 'a' || a[i] == 'e' || a[i] == 'i' || a[i] == 'o' ||
        a[i] == 'u' || a[i] == 'y' || a[i] == 'A' || a[i] == 'E' ||
        a[i] == 'I' || a[i] == 'O' || a[i] == 'U' || a[i] == 'Y') {
      continue;
    } else {
      ans += '.';
      ans += towlower(a[i]);
    }
  }
  cout << ans;
}
