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more presolve, kills assignment6

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This commit is contained in:
lperron@google.com
2012-09-03 14:17:42 +00:00
parent 309c501194
commit f09ec03bf4
1 changed files with 78 additions and 0 deletions
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78
src/flatzinc/parser.cc
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@@ -265,6 +265,18 @@ void ParserState::MarkComputedVariables(CtSpec* const spec,
computed->insert(Copy(array_variables->a[0]));
VLOG(1) << " - " << array_variables->a[0]->DebugString();
}
if (array_coefficients->a[0]->getInt() == 1) {
for (int i = 1; i < size; ++i) {
if (array_coefficients->a[i]->getInt() > 0) {
return;
}
}
// Can mark the first one, this is a hidden sum.
VLOG(1) << "Marking " << spec->DebugString();
AstArray* const array_variables = spec->Arg(1)->getArray();
computed->insert(Copy(array_variables->a[0]));
VLOG(1) << " - " << array_variables->a[0]->DebugString();
}
}
}
@@ -1189,6 +1201,39 @@ bool ParserState::PresolveOneConstraint(CtSpec* const spec) {
spec->SetId("int_lin_ge");
return true;
}
// Check for all positive to do bound propagation.
bool all_positive = true;
AstArray* const array_variables = spec->Arg(1)->getArray();
for (int i = 0; i < size; ++i) {
if (array_coefficients->a[i]->getInt() < 0) {
all_positive = false;
break;
IntVarSpec* const spec =
int_variables_[array_variables->a[i]->getIntVar()];
if (!spec->HasDomain() ||
!spec->Domain()->interval ||
spec->Domain()->imin < 0) {
all_positive = false;
break;
}
}
}
if (all_positive && rhs > 0) {
for (int i = 0; i < size; ++i) {
IntVarSpec* const spec =
int_variables_[array_variables->a[i]->getIntVar()];
const int64 vmax = spec->Domain()->imax;
const int64 vcoeff = array_coefficients->a[i]->getInt();
if (vcoeff > 0) {
const int64 bound = rhs / vcoeff;
if (vmax > bound) {
VLOG(1) << " - presolve: merge " << spec->DebugString()
<< " with 0.." << bound;
spec->MergeBounds(0, bound);
}
}
}
}
}
if (id == "int_lin_le_reif") {
AstArray* const array_coefficients = spec->Arg(0)->getArray();
@@ -1284,6 +1329,39 @@ bool ParserState::PresolveOneConstraint(CtSpec* const spec) {
spec->Arg(2)->setInt(-spec->Arg(2)->getInt());
return true;
}
// Check for all positive to do bound propagation.
bool all_positive = true;
AstArray* const array_variables = spec->Arg(1)->getArray();
for (int i = 0; i < size; ++i) {
if (array_coefficients->a[i]->getInt() < 0) {
all_positive = false;
break;
IntVarSpec* const spec =
int_variables_[array_variables->a[i]->getIntVar()];
if (!spec->HasDomain() ||
!spec->Domain()->interval ||
spec->Domain()->imin < 0) {
all_positive = false;
break;
}
}
}
if (all_positive && rhs > 0) {
for (int i = 0; i < size; ++i) {
IntVarSpec* const spec =
int_variables_[array_variables->a[i]->getIntVar()];
const int64 vmax = spec->Domain()->imax;
const int64 vcoeff = array_coefficients->a[i]->getInt();
if (vcoeff > 0) {
const int64 bound = rhs / vcoeff;
if (vmax > bound) {
VLOG(1) << " - presolve: merge " << spec->DebugString()
<< " with 0.." << bound;
spec->MergeBounds(0, bound);
}
}
}
}
}
if (id == "int_lin_eq_reif") {
AstArray* const array_coefficients = spec->Arg(0)->getArray();