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simplify and filter MakeMember(x * constant, values)

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lperron@google.com
2014-05-25 01:28:47 +00:00
parent fd4f7bf8c7
commit 08269e4ab0
1 changed files with 21 additions and 14 deletions
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35
src/constraint_solver/expr_cst.cc
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@@ -1054,17 +1054,29 @@ class NotMemberCt : public Constraint {
};
} // namespace
Constraint* Solver::MakeMemberCt(IntExpr* const var,
Constraint* Solver::MakeMemberCt(IntExpr* const expr,
const std::vector<int64>& values) {
IntExpr* sub = nullptr;
int64 coef = 1;
if (IsProduct(expr, &sub, &coef) && coef != 0 && coef != 1) {
std::vector<int64> new_values;
new_values.reserve(values.size());
for (const int64 value : values) {
if (value % coef == 0) {
new_values.push_back(value / coef);
}
}
return MakeMemberCt(sub, new_values);
}
std::vector<int64> sorted = SortedNoDuplicates(values);
if (IsIncreasingContiguous(sorted)) {
return MakeBetweenCt(var, sorted.front(), sorted.back());
return MakeBetweenCt(expr, sorted.front(), sorted.back());
} else {
// Let's build the reverse vector.
if (var->Max() - var->Min() < 2 * values.size()) {
if (expr->Max() - expr->Min() < 2 * values.size()) {
hash_set<int64> value_set(values.begin(), values.end());
std::vector<int64> remaining;
for (int64 value = var->Min(); value <= var->Max(); ++value) {
for (int64 value = expr->Min(); value <= expr->Max(); ++value) {
if (!ContainsKey(value_set, value)) {
remaining.push_back(value);
}
@@ -1072,23 +1084,18 @@ Constraint* Solver::MakeMemberCt(IntExpr* const var,
if (remaining.empty()) {
return MakeTrueConstraint();
} else if (remaining.size() == 1) {
return MakeNonEquality(var, remaining.back());
return MakeNonEquality(expr, remaining.back());
} else if (remaining.size() < values.size()) {
return RevAlloc(new NotMemberCt(this, var->Var(), remaining));
return RevAlloc(new NotMemberCt(this, expr->Var(), remaining));
}
}
return RevAlloc(new MemberCt(this, var->Var(), sorted));
return RevAlloc(new MemberCt(this, expr->Var(), sorted));
}
}
Constraint* Solver::MakeMemberCt(IntExpr* const var,
Constraint* Solver::MakeMemberCt(IntExpr* const expr,
const std::vector<int>& values) {
std::vector<int64> sorted = SortedNoDuplicates(ToInt64Vector(values));
if (IsIncreasingContiguous(sorted)) {
return MakeBetweenCt(var, sorted.front(), sorted.back());
} else {
return RevAlloc(new MemberCt(this, var->Var(), sorted));
}
return MakeMemberCt(expr, ToInt64Vector(values));
}
// ----- IsMemberCt -----