#include <bits/stdc++.h>
using namespace std;
char s;
int main() {
  while (cin >> s) {
    s = tolower(s);
    if (!(s == 'e' || s == 'a' || s == 'y' || s == 'u' || s == 'o' ||
          s == 'i')) {
      cout << "." << s;
    }
  }
}
