#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  int n, i, d = 0;
  n = s.length();
  for (i = 0; i < n; i++) {
    s[i] = towupper(s[i]);
    s[i] = s[i] + 32;
    if (s[i] == 'a' || s[i] == 'o' || s[i] == 'y' || s[i] == 'e' ||
        s[i] == 'u' || s[i] == 'i')
      d++;
    else
      cout << "." << s[i];
  }
  return 0;
}
