public void Unite(UnionFindNode<T> other) {
UnionFindNode<T> a = this.Find();
UnionFindNode<T> b = other.Find();
if (a != b) {
// need to unite a and b - a will be parent of b
int aSize = a.subNodes == null ? 1 : a.subNodes.Count;
int bSize = b.subNodes == null ? 1 : b.subNodes.Count;
if (aSize < bSize) { // a is smaller, so it should be child
UnionFindNode<T> t = a;
a = b;
b = t;
}
b.parent = a;
if (a.subNodes == null) {
a.subNodes = new List<UnionFindNode<T>>();
a.subNodes.Add(a);
}
if (b.subNodes == null) {
a.subNodes.Add(b);
} else {
foreach (UnionFindNode<T> bn in b.subNodes) {
a.subNodes.Add(bn);
}
b.subNodes = null;
}
allRoots.Remove(b);
}
}
public UnionFind(IEnumerable <T> values)
{
foreach (T value in values)
{
UnionFindNode <T> n = new UnionFindNode <T>(roots, value);
nodes.Add(n);
nodeMap[value] = n;
roots.Add(n);
}
}
public IEnumerable<UnionFindNode<T>> GetSetMembers() {
UnionFindNode<T> a = this.Find();
if (a.subNodes == null) {
List<UnionFindNode<T>> result = new List<UnionFindNode<T>>();
result.Add(a);
a.subNodes = result;
return result;
} else {
return a.subNodes;
}
}
private UnionFindNode<T> Find() {
UnionFindNode<T> ret = this.parent;
if (ret == null) {
return this;
} else {
UnionFindNode<T> next = ret.parent;
while (next != null) {
ret = next;
next = ret.parent;
}
this.parent = ret;
return ret;
}
}
public bool IsInSameSet(UnionFindNode<T> other) {
return this.Find() == other.Find();
}