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