int128 setup

using int128 = __int128;

std::istream& operator >> (std::istream& stream, int128& x) {
  long long t;
  stream >> t;
  x = t;
  return stream;
}

std::ostream& operator << (std::ostream& stream, int128 x) {
  if (x < 0) {
    stream << "-";
    x = -x;
  }
  std::string s;
  while (x != 0) {
    s += char('0' + x % 10);
    x /= 10;
  }
  if (s.empty()) {
    s += '0';
  }
  std::reverse(s.begin(), s.end());
  return stream << s;
}