private int KruskalRoutine(List <Edge1> edges)
{
/* Start picking and adding edges to the UnionFind
* without creating cycles. Stop when UnionFind components
* become 'k'-clusters.
*/
// Initialize UnionFind
UnionFind uf = new UnionFind(EdgeBuilder.ExtractVertices(edges));
int maxSpacing = 0;
foreach (Edge1 edge in edges)
{
// If the vertices (clusters) are in different components, add.
if (uf.Find(edge.U) != uf.Find(edge.V))
{
// Check if k-cluster reached
if (uf.Components == _k)
{
maxSpacing = edge.Cost;
break;
}
uf.Union(edge.U, edge.V);
}
}
return(maxSpacing);
}
public static UnionFind CopyUnionFind(UnionFind input)
{
var n = input.Nodes.Length;
var output = new UnionFind
{
Nodes = new int[n],
Sizes = new int[n]
};
input.Nodes.CopyTo(output.Nodes, 0);
input.Sizes.CopyTo(output.Sizes, 0);
return(output);
}
public int Execute(string filepath)
{
int maxVertex = 199999;
// Sample dict format <234123, "1001010010101001001~23,779, ..">
Dictionary <int, string> graph = BuildGraph(filepath);
// Will initialize Union Find to max vertex as 0-199999 already known
_uf = new UnionFind(maxVertex);
GetMaxClustersPossible(graph);
// At the end, simply count the UF components
return(_uf.Components);
}