#include <bits/stdc++.h>
using namespace std;
int main() {
  char s[1000], s1[1000];
  int i, j, l;
  scanf("%s", &s);
  l = strlen(s);
  for (i = 0; i < l; i++)
    if (s[i] < 91) s[i] = s[i] + 32;
  j = 1;
  for (i = 0; i < l; i++)
    if (!((s[i] == 'a') || (s[i] == 'e') || (s[i] == 'i') || (s[i] == 'o') ||
          (s[i] == 'u') || (s[i] == 'y'))) {
      s1[j - 1] = '.';
      s1[j] = s[i];
      j = j + 2;
    }
  s1[j - 1] = '\0';
  printf("%s\n", s1);
}
