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