1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
// SPDX-License-Identifier: GPL-2.0
#include <linux/union_find.h>
/**
* uf_find - Find the root of a node and perform path compression
* @node: the node to find the root of
*
* This function returns the root of the node by following the parent
* pointers. It also performs path compression, making the tree shallower.
*
* Returns the root node of the set containing node.
*/
struct uf_node *uf_find(struct uf_node *node)
{
struct uf_node *parent;
while (node->parent != node) {
parent = node->parent;
node->parent = parent->parent;
node = parent;
}
return node;
}
/**
* uf_union - Merge two sets, using union by rank
* @node1: the first node
* @node2: the second node
*
* This function merges the sets containing node1 and node2, by comparing
* the ranks to keep the tree balanced.
*/
void uf_union(struct uf_node *node1, struct uf_node *node2)
{
struct uf_node *root1 = uf_find(node1);
struct uf_node *root2 = uf_find(node2);
if (root1 == root2)
return;
if (root1->rank < root2->rank) {
root1->parent = root2;
} else if (root1->rank > root2->rank) {
root2->parent = root1;
} else {
root2->parent = root1;
root1->rank++;
}
}
|
