1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_UNION_FIND_H
3 #define __LINUX_UNION_FIND_H
4 /**
5 * union_find.h - union-find data structure implementation
6 *
7 * This header provides functions and structures to implement the union-find
8 * data structure. The union-find data structure is used to manage disjoint
9 * sets and supports efficient union and find operations.
10 *
11 * See Documentation/core-api/union_find.rst for documentation and samples.
12 */
13
14 struct uf_node {
15 struct uf_node *parent;
16 unsigned int rank;
17 };
18
19 /* This macro is used for static initialization of a union-find node. */
20 #define UF_INIT_NODE(node) {.parent = &node, .rank = 0}
21
22 /**
23 * uf_node_init - Initialize a union-find node
24 * @node: pointer to the union-find node to be initialized
25 *
26 * This function sets the parent of the node to itself and
27 * initializes its rank to 0.
28 */
29 static inline void uf_node_init(struct uf_node *node)
30 {
31 node->parent = node;
32 node->rank = 0;
33 }
34
35 /* find the root of a node */
36 struct uf_node *uf_find(struct uf_node *node);
37
38 /* Merge two intersecting nodes */
39 void uf_union(struct uf_node *node1, struct uf_node *node2);
40
41 #endif /* __LINUX_UNION_FIND_H */
42
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