#include <bits/stdc++.h>
using namespace std;
int main() {
  string str, str1;
  cin >> str;
  for (int i = 0; i < str.size(); i++) {
    char c = tolower(str[i]);
    if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' || c == 'y') {
      continue;
    } else {
      cout << "." << c;
    }
  }
  cout << str1;
  return 0;
}
