public int PermanentRandomization()
{
RNGCrypto rand = new RNGCrypto();
int e1 = rand.Next(0, existingEdges.Count - 1);
int e2 = rand.Next(0, existingEdges.Count - 1);
while (e1 == e2 ||
existingEdges[e1].Key == existingEdges[e2].Key ||
existingEdges[e1].Value == existingEdges[e2].Value ||
existingEdges[e1].Key == existingEdges[e2].Value ||
existingEdges[e1].Value == existingEdges[e2].Key ||
AreConnected(existingEdges[e1].Key, existingEdges[e2].Key) ||
AreConnected(existingEdges[e1].Value, existingEdges[e2].Value))
{
e1 = rand.Next(0, existingEdges.Count - 1);
e2 = rand.Next(0, existingEdges.Count - 1);
}
int vertex1 = existingEdges[e1].Key, vertex2 = existingEdges[e1].Value;
int vertex3 = existingEdges[e2].Key, vertex4 = existingEdges[e2].Value;
RemoveConnection(vertex1, vertex2);
RemoveConnection(vertex3, vertex4);
// Calculate removed cycles count
int removedCyclesCount = Cycles3ByVertices(vertex1, vertex2) +
Cycles3ByVertices(vertex3, vertex4);
AddConnection(vertex1, vertex3);
AddConnection(vertex2, vertex4);
// Calculate removed cycles count
int addedCyclesCount = Cycles3ByVertices(vertex1, vertex3) +
Cycles3ByVertices(vertex2, vertex4);
return addedCyclesCount - removedCyclesCount;
}
public int NonPermanentRandomization()
{
RNGCrypto rand = new RNGCrypto();
int edgeToRemove = rand.Next(0, existingEdges.Count - 1);
int rvertex1 = existingEdges[edgeToRemove].Key;
int rvertex2 = existingEdges[edgeToRemove].Value;
int edgeToAdd = rand.Next(0, nonExistingEdges.Count - 1);
int avertex1 = nonExistingEdges[edgeToAdd].Key;
int avertex2 = nonExistingEdges[edgeToAdd].Value;
RemoveConnection(rvertex1, rvertex2);
// Calculate removed cycles count
int removedCyclesCount = Cycles3ByVertices(rvertex1, rvertex2);
AddConnection(avertex1, avertex2);
// Calculate removed cycles count
int addedCyclesCount = Cycles3ByVertices(avertex1, avertex2);
return addedCyclesCount - removedCyclesCount;
}