#include <bits/stdc++.h>
int main() {
  char str[100];
  scanf("%s", &str);
  for (int i = 0; str[i] != '\0'; i++) {
    if (str[i] >= 65 && str[i] <= 90) {
      str[i] += 32;
    }
    if (str[i] != 'a' && str[i] != 'e' && str[i] != 'i' && str[i] != 'o' &&
        str[i] != 'u' && str[i] != 'y') {
      printf(".%c", str[i]);
    }
  }
}
