13-binary_tree_nodes.c

#include "binary_trees.h"

/**
 * is_leaf - function that checks if a node is a leaf.
 * @node: pointer to the node to check.
 *
 * Return: 1 if node is a leaf, else
 *          0 if not a leaf or node is NULL.
 */

int is_leaf(const binary_tree_t *node)
{
	if (node != NULL && node->left == NULL && node->right == NULL)
		return (1);
	return (0);
}

/**
 * binary_tree_nodes - counts the nodes with at least 1 child in a binary tree
 * @tree: pointer to the root node of the tree
 * Return: the count, or 0 if tree is NULL
 */

size_t binary_tree_nodes(const binary_tree_t *tree)
{
	size_t left, right, total;

	if (tree == NULL || is_leaf(tree))
		return (0);
	left = binary_tree_nodes(tree->left);
	right = binary_tree_nodes(tree->right);
	total = left + right + 1;

	return (total);
}