#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  string t = "";
  for (int i = 0; i < s.length(); i++) {
    if (s[i] != 'a' && s[i] != 'e' && s[i] != 'i' && s[i] != 'o' &&
        s[i] != 'u' && s[i] != 'y' && s[i] != 'Y' && s[i] != 'A' &&
        s[i] != 'E' && s[i] != 'I' && s[i] != 'O' && s[i] != 'U') {
      t += s[i];
    }
  }
  string p = "";
  for (int i = 0; i < t.length(); i++) {
    char c = t[i];
    if (isupper(c)) {
      p += tolower(c);
    } else {
      p += c;
    }
  }
  string l = "";
  for (int i = 0; i < p.length(); i++) {
    l += '.';
    l += p[i];
  }
  cout << l;
}
