#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  int len = s.length();
  for (int i = 0; i < len; i = i + 1) {
    if (s[i] != 'a' && s[i] != 'y' && s[i] != 'e' && s[i] != 'i' &&
        s[i] != 'o' && s[i] != 'u' && s[i] != 'A' && s[i] != 'Y' &&
        s[i] != 'E' && s[i] != 'I' && s[i] != 'O' && s[i] != 'U') {
      if (s[i] >= 'A' && s[i] <= 'Z') {
        s[i] = s[i] + 32;
      }
      cout << "." << s[i];
    }
  }
  cout << endl;
  return 0;
}
