#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  string result;
  for (int i = 0; i < s.size(); i++) {
    if (s[i] <= 90) s[i] += 32;
    if (s[i] == 'a' || s[i] == 'o' || s[i] == 'i' || s[i] == 'u' ||
        s[i] == 'e' || s[i] == 'y')
      continue;
    else {
      result.push_back('.');
      result.push_back(s[i]);
    }
  }
  cout << result;
}
