#include <bits/stdc++.h>
using namespace std;
int main() {
  char s[200] = {NULL};
  char temp[200] = {NULL};
  int i, j;
  cin >> s;
  int l = strlen(s);
  for (i = 0, j = 0; i < l; i++) {
    if (s[i] == 'a' || s[i] == 'A' || s[i] == 'e' || s[i] == 'E' ||
        s[i] == 'i' || s[i] == 'I' || s[i] == 'o' || s[i] == 'O' ||
        s[i] == 'u' || s[i] == 'U' || s[i] == 'y' || s[i] == 'Y') {
      continue;
    } else if (s[i] >= 'A' && s[i] <= 'Z') {
      temp[j++] = '.';
      temp[j++] = s[i] + 32;
    } else {
      temp[j++] = '.';
      temp[j++] = s[i];
    }
  }
  temp[j] = NULL;
  cout << temp << endl;
}
