static void color_tree_cleanup(ColorTree* tree)
{
  int i;
  for(i = 0; i < 16; i++)
  {
    if(tree->children[i])
    {
      color_tree_cleanup(tree->children[i]);
      free(tree->children[i]);
    }
  }
}
static void color_tree_cleanup(ColorTree* tree)
{
  int i;
  for(i = 0; i < 16; i++)
  {
    if(tree->children[i])
    {
      color_tree_cleanup(tree->children[i]);
      free(tree->children[i]);
    }
  }
}