#include <bits/stdc++.h>
using namespace std;
const int N = 300;
int main() {
  char str[N], res[N] = {0};
  int cnt = 0;
  scanf("%s", str);
  int len = strlen(str);
  for (int i = 0; i < len; i++) str[i] = tolower(str[i]);
  for (int i = 0; i < len; i++) {
    if (str[i] == 'a' || str[i] == 'o' || str[i] == 'e' || str[i] == 'i' ||
        str[i] == 'u' || str[i] == 'y')
      continue;
    else {
      res[cnt++] = '.';
      res[cnt++] = str[i];
    }
  }
  puts(res);
  return 0;
}
