void _AddVertexToDegList(ColorVerticesContext *context, graphP theGraph, int v, int deg)
{
if (deg > 0)
{
if (_IsConstantTimeContractible(context, v))
context->degListHeads[deg] = LCPrepend(context->degLists, context->degListHeads[deg], v);
else
context->degListHeads[deg] = LCAppend(context->degLists, context->degListHeads[deg], v);
context->numVerticesToReduce++;
}
context->degree[v] = deg;
}
void _K33Search_CreateDFSTreeEmbedding(graphP theGraph)
{
K33SearchContext *context = NULL;
gp_FindExtension(theGraph, K33SEARCH_ID, (void *)&context);
if (context != NULL)
{
// When searching for K_{3,3} homeomorphs, we need the
// list of DFS children for each vertex, which gets lost
// during the initial tree embedding (each DFS tree child
// arc is moved to the root copy of the vertex)
if (theGraph->embedFlags == EMBEDFLAGS_SEARCHFORK33)
{
int I, J, N;
N = theGraph->N;
for (I=0; I<N; I++)
{
J = gp_GetFirstArc(theGraph, I);
// If a vertex has any DFS children, the edges
// to them are stored in descending order of
// the DFI's along the successor arc pointers, so
// we traverse them and prepend each to the
// ascending order sortedDFSChildList
while (theGraph->G[J].type == EDGE_DFSCHILD)
{
context->V[I].sortedDFSChildList =
LCPrepend(context->sortedDFSChildLists,
context->V[I].sortedDFSChildList,
theGraph->G[J].v);
J = gp_GetNextArc(theGraph, J);
}
}
}
// Invoke the superclass version of the function
context->functions.fpCreateDFSTreeEmbedding(theGraph);
}
}
void LCInsertBefore(listCollectionP listColl, int theAnchor, int theNewNode)
{
LCPrepend(listColl, theAnchor, theNewNode);
}