#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  int n = s.length();
  for (int i = 0; i < n; i++) {
    if (s[i] >= 'A' && s[i] <= 'Z') {
      s[i] += 32;
    }
  }
  for (int i = 0; i < n; i++) {
    if ((s[i] != 'a') && (s[i] != 'e') && (s[i] != 'i') && (s[i] != 'o') &&
        (s[i] != 'u') && (s[i] != 'y')) {
      cout << '.' << s[i];
    }
  }
}
