#include <bits/stdc++.h>
using namespace std;
int main() {
  string val;
  getline(cin, val);
  int i;
  char ris;
  for (i = 0; i < val.length(); i++) {
    if (val[i] != 'a' && val[i] != 'A' && val[i] != 'e' && val[i] != 'E' &&
        val[i] != 'i' && val[i] != 'I' && val[i] != 'o' && val[i] != 'O' &&
        val[i] != 'u' && val[i] != 'U' && val[i] != 'y' && val[i] != 'Y') {
      if (val[i] > 96)
        cout << '.' << val[i];
      else {
        ris = val[i] + 32;
        cout << '.' << ris;
      }
    }
  }
  return 0;
}
