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