#include <bits/stdc++.h>
using namespace std;
string s, s1;
int n, i;
int top;
int main() {
  cin >> s;
  int len = s.size();
  for (register int i = 0; i < len; i++) {
    if (s[i] >= 'A' && s[i] <= 'Z') {
      s[i] += 32;
    }
  }
  for (register int i = 0; i < len; i++) {
    if (s[i] == 'a' || s[i] == 'e' || s[i] == 'i' || s[i] == 'o' ||
        s[i] == 'u' || s[i] == 'y') {
      continue;
    }
    s1 += ".";
    s1 += s[i];
  }
  cout << s1;
  return 0;
}
