#include <bits/stdc++.h>
using namespace std;
int main() {
  string seq;
  cin >> seq;
  for (int i = 0; i < seq.length(); i++) {
    if (seq[i] == 'A' || seq[i] == 'E' || seq[i] == 'I' || seq[i] == 'O' ||
        seq[i] == 'U' || seq[i] == 'a' || seq[i] == 'e' || seq[i] == 'i' ||
        seq[i] == 'o' || seq[i] == 'u' || seq[i] == 'Y' || seq[i] == 'y') {
    } else {
      cout << '.';
      if (seq[i] >= 'A' && seq[i] <= 'Z') seq[i] += 'a' - 'A';
      cout << seq[i];
    }
  }
  cout << endl;
}
