#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  string x;
  x = "";
  int l = s.size();
  int i;
  for (i = 0; i < l; i++) {
    if (s[i] != 'a' && s[i] != 'e' && s[i] != 'o' && s[i] != 'u' &&
        s[i] != 'i' && s[i] != 'A' && s[i] != 'E' && s[i] != 'I' &&
        s[i] != 'O' && s[i] != 'U' && s[i] != 'y' && s[i] != 'Y') {
      if ((int)s[i] >= 65 && (int)s[i] <= 90) {
        s[i] = (char)((int)s[i] + 32);
      }
      x = x + s[i];
    }
  }
  int l2 = x.size();
  string new1;
  new1 = "";
  for (i = 0; i < l2; i++) {
    new1 = new1 + '.';
    new1 = new1 + x[i];
  }
  cout << new1;
  return 0;
}
