#include <bits/stdc++.h>
int main() {
  char a[101], ch;
  scanf("%s", a);
  int l = strlen(a);
  int i;
  for (i = 0; i < l; i++) {
    ch = a[i];
    if (ch != 'A' && ch != 'O' && ch != 'Y' && ch != 'E' && ch != 'U' &&
        ch != 'I' && ch != 'a' && ch != 'o' && ch != 'y' && ch != 'e' &&
        ch != 'u' && ch != 'i') {
      if (ch >= 'A' && ch <= 'Z') {
        ch = 'a' + (ch - 'A');
      }
      printf(".%c", ch);
    }
  }
  return 0;
}
