#include <bits/stdc++.h>
using namespace std;
int main() {
  char a[100];
  cin >> a;
  int n = strlen(a);
  for (int i = 0; i < n; i++) a[i] = tolower(a[i]);
  int i = 0;
  while (i < n) {
    if (a[i] != 'a' && a[i] != 'e' && a[i] != 'i' && a[i] != 'o' &&
        a[i] != 'u' && a[i] != 'y') {
      cout << "." << a[i];
    }
    i++;
  }
  cout << endl;
  return 0;
}
