static void KarpPartition(int start, int end, int last_mid)
{
int i;
if (end - start + 1 <= SubproblemSize) {
if (last_mid <= start)
start = last_mid;
else
end = last_mid;
CurrentSubproblem++;
for (i = start; i <= end; i++)
KDTree[i]->Subproblem = CurrentSubproblem;
OldGlobalBestCost = GlobalBestCost;
SolveSubproblem(CurrentSubproblem, Subproblems, &GlobalBestCost);
if (SubproblemsCompressed && GlobalBestCost == OldGlobalBestCost) {
if (TraceLevel >= 1)
printff("\nCompress subproblem %d:\n", CurrentSubproblem);
RestrictedSearch = 0;
SolveSubproblem(CurrentSubproblem, Subproblems,
&GlobalBestCost);
RestrictedSearch = RestrictedSearchSaved;
}
} else {
int mid = (start + end) / 2;
KarpPartition(start, mid - 1, mid);
KarpPartition(mid + 1, end, mid);
}
}
static void KarpPartition(int start, int end)
{
if (end - start + 1 <= SubproblemSize) {
int i;
CurrentSubproblem++;
for (i = start; i <= end; i++)
KDTree[i]->Subproblem = CurrentSubproblem;
OldGlobalBestCost = GlobalBestCost;
SolveSubproblem(CurrentSubproblem, Subproblems, &GlobalBestCost);
if (SubproblemsCompressed && GlobalBestCost == OldGlobalBestCost)
SolveCompressedSubproblem(CurrentSubproblem, Subproblems,
&GlobalBestCost);
} else {
int mid = (start + end) / 2;
KarpPartition(start, mid);
KarpPartition(mid + 1, end);
}
}
void SolveKarpSubproblems()
{
Node *N;
int i;
double EntryTime = GetTime();
AllocateStructures();
ReadPenalties();
/* Compute upper bound for the original problem */
GlobalBestCost = 0;
N = FirstNode;
do {
if (!Fixed(N, N->SubproblemSuc))
GlobalBestCost += Distance(N, N->SubproblemSuc);
N->Subproblem = 0;
}
while ((N = N->BestSuc = N->SubproblemSuc) != FirstNode);
if (TraceLevel >= 1) {
if (TraceLevel >= 2)
printff("\n");
printff("*** Karp partitioning *** [Cost = " GainFormat "]\n",
GlobalBestCost);
}
if (WeightType == GEO || WeightType == GEOM ||
WeightType == GEO_MEEUS || WeightType == GEOM_MEEUS) {
N = FirstNode;
do {
N->Xc = N->X;
N->Yc = N->Y;
N->Zc = N->Z;
if (WeightType == GEO || WeightType == GEO_MEEUS)
GEO2XYZ(N->Xc, N->Yc, &N->X, &N->Y, &N->Z);
else
GEOM2XYZ(N->Xc, N->Yc, &N->X, &N->Y, &N->Z);
} while ((N = N->SubproblemSuc) != FirstNode);
CoordType = THREED_COORDS;
}
KDTree = BuildKDTree();
if (WeightType == GEO || WeightType == GEOM ||
WeightType == GEO_MEEUS || WeightType == GEOM_MEEUS) {
N = FirstNode;
do {
N->X = N->Xc;
N->Y = N->Yc;
N->Z = N->Zc;
} while ((N = N->SubproblemSuc) != FirstNode);
CoordType = TWOD_COORDS;
}
CurrentSubproblem = 0;
Subproblems = 1;
for (i = Dimension - 1; i > SubproblemSize; i /= 2)
Subproblems *= 2;
RestrictedSearchSaved = RestrictedSearch;
KarpPartition(0, Dimension - 1, 0);
free(KDTree);
printff("\nCost = " GainFormat, GlobalBestCost);
if (Optimum != MINUS_INFINITY && Optimum != 0)
printff(", Gap = %0.3f%%",
100.0 * (GlobalBestCost - Optimum) / Optimum);
printff(", Time = %0.1f sec. %s\n", fabs(GetTime() - EntryTime),
GlobalBestCost < Optimum ? "<" : GlobalBestCost ==
Optimum ? "=" : "");
if (SubproblemBorders && Subproblems > 1)
SolveSubproblemBorderProblems(Subproblems);
}