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