#include <bits/stdc++.h>
int main() {
  char cad[105];
  scanf("%s", cad);
  int i = 0;
  while (cad[i] != '\0') {
    cad[i] = tolower(cad[i]);
    if (cad[i] != 'a' && cad[i] != 'e' && cad[i] != 'i' && cad[i] != 'o' &&
        cad[i] != 'u' && cad[i] != 'y') {
      printf(".%c", cad[i]);
    }
    i++;
  }
  printf("\n");
  return 0;
}
