#include <bits/stdc++.h>
using namespace std;
const int P = 10101;
char c[P], ans[P];
int main() {
  cin >> c;
  int t = strlen(c);
  for (int i = 0; i < t; i++) {
    if (c[i] <= 'Z' && c[i] >= 'A') c[i] += 'a' - 'A';
    if (!(c[i] == 'a' || c[i] == 'o' || c[i] == 'y' || c[i] == 'e' ||
          c[i] == 'u' || c[i] == 'i'))
      cout << "." << c[i];
  }
}
