#include <bits/stdc++.h>
int main() {
  char str[100];
  int i;
  gets(str);
  for (i = 0; str[i]; i++) {
    if (str[i] >= 65 && str[i] <= 92) {
      str[i] = str[i] + 32;
    }
    if (str[i] == 'a' || str[i] == 'e' || str[i] == 'i' || str[i] == 'o' ||
        str[i] == 'u' || str[i] == 'y') {
      printf("");
    } else {
      printf(".%c", str[i]);
    }
  }
  return 0;
}
