98 lines
2.5 KiB
Text
98 lines
2.5 KiB
Text
Red-Black Tree
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--------------
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Macros
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~~~~~~
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`RB_RED`::
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`RB_BLACK`::
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Used to mark the color of a `rbnode`.
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`RBTREE_INIT`::
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Initialize a `rbtree` structure. +
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should only be used with the declaration like:
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+
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----
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rbtree tree = RBTREE_INIT(...);
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----
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+
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the arguments are pointers to callback functions, in order: `delete_fn`, `update_fn`, `cmp_fn`
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Data structures
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~~~~~~~~~~~~~~~
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* `rbnode`
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+
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--
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The binary tree node.
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`key`::
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The key of this node
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`child`::
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pointers to the left and right child to this node
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`color`::
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the color, should be a value of `RB_BLACK` or `RB_RED`
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--
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++++
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++++
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* `rbtree`
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+
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--
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Structure that holds a tree of nodes
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`root`::
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Pointer to the node that is the root of the tree.
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`delete_fn`::
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Pointer to the function that should handle the delete routines for the `rbnode->key` pointer.
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`update_fn`::
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Pointer to the function that is called when the implementation performs an update of an `rbnode->key` pointer. +
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The function gets the following information passed in order: old pointer, new pointer.
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NOTE: You may only need this if you store the data in another structure and has to keep it synchronized with the RB-tree.
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`cmp_fn`::
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Pointer to the function that is used to compare two `rbnode->key` pointers. +
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Shall return a value greater than zero if 'ptr1' > 'ptr2', a value less than zero if 'ptr1' < 'ptr2' and zero if 'ptr1' == 'ptr2'.
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--
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Functions
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~~~~~~~~~
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`rbtree_insert()`::
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Creates and inserts a new node in the tree. +
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If provided, calls `rbtree->update_fn` and `rbtree->delete_fn` if a node should be updated. +
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Returns nonzero if a new node was inserted or updated, zero otherwise.
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NOTE: The memory pointed to by the 'key' pointer is *not* copied so you must ensure that it has a infinite lifetime.
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`rbtree_delete()`::
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Deletes a node from the tree. if provided, calls `rbtree->delete_fn` for the node. +
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Returns nonzero if a node was removed, zero otherwise.
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`rbtree_free()`::
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Deletes the whole tree. if provided, calls `rbtree->delete_fn` for every node.
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`rbtree_walk()`::
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Walks the tree in-order and passes a pointer to `rbnode->key`
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for the given node to the 'action' callback function.
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`rbtree_search()`::
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Searches the tree for 'key'. +
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Returns a pointer to the node if found else `NULL`.
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NOTE: the function uses the `rbtree->cmp_fn` function to compare 'key' with a `rbnode->key`.
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`rbtree_is_empty()`::
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Checks if a tree is empty, retruns zero if the tree is empty, nonzero otherwise.
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