function to find the uncle of a node in a tree

18-binary_tree_uncle.c

@@ -0,0 +1,20 @@
+#include "binary_trees.h"
+
+/**
+ * binary_tree_uncle - Finds the uncle of a node
+ *                     in a binary tree.
+ * @node: A pointer to the node to find the uncle of.
+ *
+ * Return: If node is NULL or has no uncle, NULL.
+ *         Otherwise, a pointer to the uncle node.
+ */
+binary_tree_t *binary_tree_uncle(binary_tree_t *node)
+{
+	if (node == NULL ||
+	    node->parent == NULL ||
+	    node->parent->parent == NULL)
+		return (NULL);
+	if (node->parent->parent->left == node->parent)
+		return (node->parent->parent->right);
+	return (node->parent->parent->left);
+}

binary_trees.h

@@ -31,5 +31,21 @@ void binary_tree_print(const binary_tree_t *);
 binary_tree_t *binary_tree_node(binary_tree_t *parent, int value);
 binary_tree_t *binary_tree_insert_left(binary_tree_t *parent, int value);
 binary_tree_t *binary_tree_insert_right(binary_tree_t *parent, int value);
+void binary_tree_delete(binary_tree_t *tree);
+int binary_tree_is_leaf(const binary_tree_t *node);
+int binary_tree_is_root(const binary_tree_t *node);
+void binary_tree_preorder(const binary_tree_t *tree, void (*func)(int));
+void binary_tree_inorder(const binary_tree_t *tree, void (*func)(int));
+void binary_tree_postorder(const binary_tree_t *tree, void (*func)(int));
+size_t binary_tree_height(const binary_tree_t *tree);
+size_t binary_tree_depth(const binary_tree_t *tree);
+size_t binary_tree_size(const binary_tree_t *tree);
+size_t binary_tree_leaves(const binary_tree_t *tree);
+size_t binary_tree_nodes(const binary_tree_t *tree);
+int binary_tree_balance(const binary_tree_t *tree);
+int binary_tree_is_full(const binary_tree_t *tree);
+int binary_tree_is_perfect(const binary_tree_t *tree);
+binary_tree_t *binary_tree_sibling(binary_tree_t *node);
+binary_tree_t *binary_tree_uncle(binary_tree_t *node);
 
 #endif /* BINARY_TREES_H */