Acid
87 lines
1.6 KiB
Go
87 lines
1.6 KiB
Go
package sets
|
|
|
|
// UnionFind {
|
|
// disjointed int
|
|
// parent []int
|
|
// rank []int
|
|
// }
|
|
type UnionFind struct {
|
|
disjointed int
|
|
parent []int
|
|
rank []int
|
|
}
|
|
|
|
// NewUnionFind() -> Creates an disjoint set ,takes the unique elements as parameter.
|
|
func NewUnionFind(uniqueElements int) *UnionFind {
|
|
// counts from 0 correction
|
|
uniqueElements += 1
|
|
|
|
uf := &UnionFind{
|
|
parent: make([]int, uniqueElements),
|
|
rank: make([]int, uniqueElements),
|
|
disjointed: uniqueElements - 1,
|
|
}
|
|
|
|
for i := range uf.parent {
|
|
uf.parent[i] = i
|
|
}
|
|
|
|
return uf
|
|
}
|
|
|
|
// Find() -> returns the root of a node
|
|
func (uf *UnionFind) Find(val int) int {
|
|
root := val
|
|
|
|
// find root of val
|
|
for uf.parent[root] != root {
|
|
root = uf.parent[root]
|
|
}
|
|
|
|
// point every node on the path directly at root
|
|
current := val
|
|
for uf.parent[current] != root {
|
|
current, uf.parent[current] = uf.parent[current], root
|
|
}
|
|
|
|
return root
|
|
}
|
|
|
|
// Union() -> creates an Union of 2 values, returns true if success
|
|
func (uf *UnionFind) Union(a int, b int) bool {
|
|
node1 := uf.Find(a)
|
|
node2 := uf.Find(b)
|
|
|
|
if node1 == node2 {
|
|
return false
|
|
}
|
|
|
|
winner, loser := node1, node2
|
|
if uf.rank[winner] < uf.rank[loser] {
|
|
winner, loser = loser, winner
|
|
}
|
|
|
|
// merge
|
|
uf.parent[loser] = winner
|
|
|
|
if uf.rank[winner] == uf.rank[loser] {
|
|
uf.rank[winner]++
|
|
}
|
|
uf.disjointed--
|
|
|
|
return true
|
|
}
|
|
|
|
// IsUnion() -> returns true if the parameters have the same root
|
|
func (uf *UnionFind) IsUnion(a int, b int) bool {
|
|
if uf.Find(a) == uf.Find(b) {
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
// Disjointed() -> returns the count of disjointed sets remaining
|
|
func (uf *UnionFind) Disjointed() int {
|
|
return uf.disjointed
|
|
}
|