void FindRoot(const Tree &tree, unsigned *ptruNode1, unsigned *ptruNode2,
double *ptrdLength1, double *ptrdLength2,
ROOT RootMethod)
{
#if TRACE
tree.LogMe();
#endif
if (tree.IsRooted())
Quit("FindRoot: tree already rooted");
const unsigned uNodeCount = tree.GetNodeCount();
const unsigned uLeafCount = tree.GetLeafCount();
if (uNodeCount < 2)
Quit("Root: don't support trees with < 2 edges");
EdgeInfo **EIs = new EdgeInfo *[uNodeCount];
for (unsigned uNodeIndex = 0; uNodeIndex < uNodeCount; ++uNodeIndex)
EIs[uNodeIndex] = new EdgeInfo[3];
EdgeList Edges;
for (unsigned uNodeIndex = 0; uNodeIndex < uNodeCount; ++uNodeIndex)
if (tree.IsLeaf(uNodeIndex))
{
unsigned uParent = tree.GetNeighbor1(uNodeIndex);
Edges.Add(uParent, uNodeIndex);
}
#if TRACE
Log("Edges: ");
Edges.LogMe();
#endif
// Main loop: iterate until all distances known
double dAllMaxDist = -1e20;
unsigned uMaxFrom = NULL_NEIGHBOR;
unsigned uMaxTo = NULL_NEIGHBOR;
for (;;)
{
EdgeList NextEdges;
#if TRACE
Log("\nTop of main loop\n");
Log("Edges: ");
Edges.LogMe();
Log("MDs:\n");
ListEIs(EIs, uNodeCount);
#endif
// For all edges
const unsigned uEdgeCount = Edges.GetCount();
if (0 == uEdgeCount)
break;
for (unsigned n = 0; n < uEdgeCount; ++n)
{
unsigned uNodeFrom;
unsigned uNodeTo;
Edges.GetEdge(n, &uNodeFrom, &uNodeTo);
CalcInfo(tree, uNodeFrom, uNodeTo, EIs);
#if TRACE
Log("Edge %u -> %u\n", uNodeFrom, uNodeTo);
#endif
const unsigned uNeighborCount = tree.GetNeighborCount(uNodeFrom);
for (unsigned i = 0; i < uNeighborCount; ++i)
{
const unsigned uNeighborIndex = tree.GetNeighbor(uNodeFrom, i);
if (!Known(tree, EIs, uNeighborIndex, uNodeFrom) &&
AllKnownOut(tree, EIs, uNeighborIndex, uNodeFrom))
NextEdges.Add(uNeighborIndex, uNodeFrom);
}
}
Edges.Copy(NextEdges);
}
#if TRACE
ListEIs(EIs, uNodeCount);
#endif
switch (RootMethod)
{
case ROOT_MidLongestSpan:
RootByMidLongestSpan(tree, EIs, ptruNode1, ptruNode2,
ptrdLength1, ptrdLength2);
break;
case ROOT_MinAvgLeafDist:
RootByMinAvgLeafDist(tree, EIs, ptruNode1, ptruNode2,
ptrdLength1, ptrdLength2);
break;
default:
Quit("Invalid RootMethod=%d", RootMethod);
}
for (unsigned uNodeIndex = 0; uNodeIndex < uNodeCount; ++uNodeIndex)
delete[] EIs[uNodeIndex];
delete[] EIs;
}
