static void Merge(Vertex a, Vertex b, int nameA, int nameB)
{
name[b] = nameA;
var c = next[b];
while (name[c] != nameA)
{
name[c] = nameA;
c = next[c];
}
size[nameA] += size[nameB];
c = next[a];
next[a] = next[b];
next[b] = c;
}
public static int SizeOf(Vertex a, Vertex b) =>
Math.Abs(a.X - b.X) + Math.Abs(a.Y - b.Y);
public Edge(Vertex a, Vertex b)
{
A = a;
B = b;
}