13-binary_tree_nodes.c

#include <stdio.h>
#include <stdlib.h>
#include "binary_trees.h"

/**
 * binary_tree_nodes - count the nodes with at least 1 child in a
 * binary tree
 *
 * @tree: pointer to the root node of the tree to count the
 * number of nodes
 *
 * Return: the number of nodes in the tree or 0 if @tree is NULL
 */
size_t binary_tree_nodes(const binary_tree_t *tree)
{
	size_t nodes;

	nodes = 1;
	if (!tree)
		return (0);
	if (!tree->right && !tree->left)
		nodes -= 1;
	nodes += binary_tree_nodes(tree->left);
	nodes += binary_tree_nodes(tree->right);

	return (nodes);
}