Is given tree foldable

/* Returns true if the given tree is foldable */

bool isFoldable(struct node *root)

{

  bool res;

 

  /* base case */

  if(root == NULL)

    return true;

 

  /* convert left subtree to its mirror */

  mirror(root->left);

 

  /* Compare the structures of the right subtree and mirrored

    left subtree */

  res = isStructSame(root->left, root->right);

 

  /* Get the originial tree back */

  mirror(root->left);

 

  return res;

}

 

bool isStructSame(struct node *a, struct node *b)

{

  if (a == NULL && b == NULL)

  {  return true; }

  if ( a != NULL && b != NULL &&

       isStructSame(a->left, b->left) &&

       isStructSame(a->right, b->right)

     )

  {  return true; }

 

  return false;

}