Check for foldable binary tree in c

C program for Check for foldable binary tree. Here problem description and other solutions.

// Include header file
#include <stdio.h>
#include <stdlib.h>

/* 
  C program for
  Check if binary tree is foldable binary tree
  Using recursion
*/
// Binary Tree Node
typedef struct TreeNode
{
	// Define useful field of TreeNode
	int data;
	struct TreeNode * left;
	struct TreeNode * right;
}TreeNode;

TreeNode * getTreeNode(int data)
{
	// Create dynamic memory of TreeNode
	TreeNode * ref = 
      (TreeNode * ) malloc(sizeof(TreeNode));
	if (ref == NULL)
	{
		// Failed to create memory 
		return NULL;
	}
	// Set node value
	ref->data = data;
	ref->left = NULL;
	ref->right = NULL;
	return ref;
}
typedef struct BinaryTree
{
	// Define useful field of BinaryTree
	struct TreeNode * root;
}BinaryTree;

BinaryTree * getBinaryTree()
{
	// Create dynamic memory of BinaryTree
	BinaryTree * ref = 
      (BinaryTree * ) malloc(sizeof(BinaryTree));
	if (ref == NULL)
	{
		// Failed to create memory 
		return NULL;
	}
	// Set initial tree root
	ref->root = NULL;
	return ref;
}
int isFoldable(TreeNode * leftRoot, 
               TreeNode * rightRoot)
{
	if (leftRoot == NULL && rightRoot == NULL)
	{
		// When both node empty
		return 1;
	}
	else if (leftRoot != NULL && rightRoot != NULL && 
             isFoldable(leftRoot->left, rightRoot->right) && 
             isFoldable(leftRoot->right, rightRoot->left))
	{
		// When
		// Valid the properties of foldable tree
		return 1;
	}
	// Fail case
	return 0;
}
// Display tree element inorder form
void inorder(TreeNode * node)
{
	if (node != NULL)
	{
		// Visit to left subtree
		inorder(node->left);
		// Print node value
		printf("  %d", node->data);
		// Visit to right subtree
		inorder(node->right);
	}
}
int main()
{
	// Create new tree
	BinaryTree * tree = getBinaryTree();
	/*
	   Binary Tree
	  -----------------------
	       5
	     /   \
	    7     4
	   /       \
	  1         2
	   \       /
	    2     5
	*/
	// Binary tree nodes
	tree->root = getTreeNode(5);
	tree->root->left = getTreeNode(7);
	tree->root->right = getTreeNode(4);
	tree->root->left->left = getTreeNode(1);
	tree->root->right->right = getTreeNode(2);
	tree->root->right->right->left = getTreeNode(5);
	tree->root->left->left->right = getTreeNode(2);
	// Display Tree elements
	inorder(tree->root);
	int result = isFoldable(tree->root->left, 
                            tree->root->right);
	if (result == 1)
	{
		printf("\n Foldable Tree\n");
	}
	else
	{
		printf("\n Not Foldable Tree\n");
	}
	/*
	         5
	       /   \
	      7     4
	     /       \
	    1         2
	     \       /
	      2     5
	       \
	        3  
	*/
	// Case 2
	tree->root->left->left->right->right = getTreeNode(3);
	inorder(tree->root);
	result = isFoldable(tree->root->left, 
                        tree->root->right);
	if (result == 1)
	{
		printf("\n Foldable Tree\n");
	}
	else
	{
		printf("\n Not Foldable Tree\n");
	}
}

Output

  1  2  7  5  4  5  2
 Foldable Tree
  1  2  3  7  5  4  5  2
 Not Foldable Tree