#include <bits/stdc++.h>
bool isVowel(char c) {
  return (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' ||
          c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U' ||
          c == 'y' || c == 'Y');
};
int main() {
  char word[100];
  scanf("%s", word);
  int i;
  int length;
  length = strlen(word);
  for (i = 0; i < length; i++) {
    if (!isVowel(word[i])) {
      printf(".%c", tolower(word[i]));
    }
  }
  return 0;
}
