public static int GetMaxClusters(IEnumerable<int> numbers, int bits, int maxSpacing)
{
var distinctNumbers = numbers.Distinct().ToArray();
int clusterCount = distinctNumbers.Length;
var numberToCluster = new Dictionary<int, int>();
for (int i = 0; i < clusterCount; i++)
{
numberToCluster.Add(distinctNumbers[i], i);
}
var unionFind = new UnionFind(clusterCount);
for (int spacing = 1; spacing <= maxSpacing; spacing++)
{
foreach (var number in distinctNumbers)
{
var modifications = GetModifications(number, bits, spacing, 0).ToArray();
foreach (var modification in modifications.Where(numberToCluster.ContainsKey))
{
var cluster1 = unionFind.Find(numberToCluster[number]);
var cluster2 = unionFind.Find(numberToCluster[modification]);
if (cluster1 != cluster2)
{
unionFind.Union(cluster1, cluster2);
clusterCount--;
}
}
}
}
return clusterCount;
}
public static int GetMaxSpacing(DirectedWeightedGraph graph, int clusterCount)
{
int currentClusterCount = graph.NodesCount;
var unionFind = new UnionFind(currentClusterCount);
var edges = new PriorityQueue<WeightedEdge, int>(graph.GetEdges().Select(e => new KeyValuePair<WeightedEdge, int>(e, e.Weight)));
while (currentClusterCount >= clusterCount)
{
var edge = edges.ExtractHighestPriorityElement();
var cluster1 = unionFind.Find(edge.StartNode);
var cluster2 = unionFind.Find(edge.EndNode);
if (cluster1 != cluster2)
{
if (currentClusterCount == clusterCount)
{
return edge.Weight;
}
unionFind.Union(cluster1, cluster2);
currentClusterCount--;
}
}
return 0;
}
public void UnionTest()
{
int n = 8;
var unionFind = new UnionFind(n);
for (int i = 0; i < n; i++)
{
unionFind.Find(i).Should().Be(i);
}
unionFind.Union(0, 1);
var group1 = unionFind.Find(0);
unionFind.Find(1).Should().Be(group1);
unionFind.Union(2, 3);
var group2 = unionFind.Find(2);
unionFind.Find(3).Should().Be(group2);
unionFind.Union(group1, group2);
var groups = new int[]
{
unionFind.Find(0),
unionFind.Find(1),
unionFind.Find(2),
unionFind.Find(3)
};
groups.Distinct().Should().HaveCount(1);
unionFind.Union(5, 6);
var largeGroup = unionFind.Find(0);
var smallGroup = unionFind.Find(5);
unionFind.Union(largeGroup, smallGroup);
unionFind.Find(5).Should().Be(largeGroup);
unionFind.Find(6).Should().Be(largeGroup);
}