readded rank/pointers union-find

Author: kafkasl

structures/union-find/union-find-rank-pointers.go

@@ -0,0 +1,50 @@
+package structures
+
+import "fmt"
+
+type UnionFindSet struct {
+parent *UnionFindSet
+rank int
+value int
+}
+
+func NewUnionFindSet(value int) *UnionFindSet {
+uf := UnionFindSet{nil, 0, value}
+uf.parent = &uf
+return &uf
+}
+
+func (uf *UnionFindSet) Find() *UnionFindSet {
+if uf.parent == uf {
+return uf
+}
+return uf.parent.Find()
+
+}
+
+func (uf *UnionFindSet) Union(other *UnionFindSet) *UnionFindSet {
+ufParent := uf.Find()
+otherParent := other.Find()
+if ufParent == otherParent {
+return ufParent
+}
+if otherParent.rank > ufParent.rank {
+ufParent.parent = otherParent
+return otherParent
+} else {
+otherParent.parent = ufParent
+if otherParent.rank == ufParent.rank {
+ufParent.rank++
+}
+return ufParent
+}
+
+}
+
+func (uf *UnionFindSet) String() string {
+if uf.parent == uf {
+return fmt.Sprintf("[%v]: %v", uf.rank, uf.value)
+}
+str := fmt.Sprintf("[%v]: %v -> %v", uf.rank, uf.value, uf.parent)
+return str
+}