include/linux/union_find.h

   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 */