#include <bits/stdc++.h>
using namespace std;
int main() {
  char s[102], S[300];
  int i = 0, j = 0;
  cin >> s;
  while (s[i] != '\0') {
    if (s[i] != 'a' && s[i] != 'e' && s[i] != 'i' && s[i] != 'o' &&
        s[i] != 'u' && s[i] != 'y' && s[i] != 'A' && s[i] != 'E' &&
        s[i] != 'I' && s[i] != 'O' && s[i] != 'U' && s[i] != 'Y') {
      if (s[i] >= 'A' && s[i] <= 'Z') {
        S[j++] = '.';
        S[j++] = s[i] + 32;
      } else {
        S[j++] = '.';
        S[j++] = s[i];
      }
    }
    i++;
  }
  S[j++] = '\0';
  cout << S << endl;
  return 0;
}
