#include <bits/stdc++.h>
int main() {
  char str[200], newstr[200];
  scanf("%s", str);
  int k = 0;
  for (int i = 0; str[i] != 0; i++) {
    if (str[i] != 'a' && str[i] != 'A' && str[i] != 'e' && str[i] != 'E' &&
        str[i] != 'i' && str[i] != 'I' && str[i] != 'o' && str[i] != 'O' &&
        str[i] != 'u' && str[i] != 'U' && str[i] != 'y' && str[i] != 'Y') {
      newstr[k] = '.';
      newstr[k + 1] = str[i] <= 90 ? str[i] + 32 : str[i];
      k += 2;
    }
  }
  for (int i = 0; i < k; i++) {
    printf("%c", newstr[i]);
  }
}
