/* For 16 bit unsigned integers. */
unsigned int round_up(unsigned int v)
{
  v--;
  v |= v >> 1;
  v |= v >> 2;
  v |= v >> 4;
  v |= v >> 8;
  v++;
  return v;
}

int main()
{
  unsigned int f;
  f = round_up(125);
  if(f == 128)
    return 5;
  else
    return 7;
}