#include <bits/stdc++.h>
using namespace std;
long long x, y, z;
string s1, s2, s;
void memset_ll(long long a[], long long v, long long n) {
  for (long long i = 0; i < n; i++) a[i] = v;
}
void memset_s(char a[], char v, long long n) {
  for (long long i = 0; i < n; i++) a[i] = v;
}
int compare(const void* a, const void* b) {
  return (*(long long*)a - *(long long*)b);
}
void q_sort(long long a[], long long n) {
  qsort(a, n, sizeof(long long), compare);
}
int main() {
  string s1;
  cin >> s1;
  transform(s1.begin(), s1.end(), s1.begin(), ::tolower);
  long long l = s1.size();
  for (long long i = l - 1; i >= 0; i--) {
    if (s1[i] == 'a' || s1[i] == 'e' || s1[i] == 'i' || s1[i] == 'o' ||
        s1[i] == 'u' || s1[i] == 'y') {
      s1.erase(s1.begin() + i);
    }
  }
  int r = s1.size();
  for (long long j = 0; j < r; j++) {
    cout << "." << s1[j];
  }
  return 0;
}
