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count_cst.cc
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count_cst.cc
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// Copyright 2010-2022 Google LLC
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Count constraints
#include <algorithm>
#include <cstdint>
#include <limits>
#include <string>
#include <utility>
#include <vector>
#include "absl/strings/str_format.h"
#include "absl/strings/str_join.h"
#include "ortools/base/integral_types.h"
#include "ortools/base/logging.h"
#include "ortools/constraint_solver/constraint_solver.h"
#include "ortools/constraint_solver/constraint_solveri.h"
#include "ortools/util/string_array.h"
namespace operations_research {
Constraint* Solver::MakeCount(const std::vector<IntVar*>& vars, int64_t value,
int64_t max_count) {
std::vector<IntVar*> tmp_sum;
for (int i = 0; i < vars.size(); ++i) {
if (vars[i]->Contains(value)) {
if (vars[i]->Bound()) {
max_count--;
} else {
tmp_sum.push_back(MakeIsEqualCstVar(vars[i], value));
}
}
}
return MakeSumEquality(tmp_sum, max_count);
}
Constraint* Solver::MakeCount(const std::vector<IntVar*>& vars, int64_t value,
IntVar* max_count) {
if (max_count->Bound()) {
return MakeCount(vars, value, max_count->Min());
} else {
std::vector<IntVar*> tmp_sum;
int64_t num_vars_bound_to_v = 0;
for (int i = 0; i < vars.size(); ++i) {
if (vars[i]->Contains(value)) {
if (vars[i]->Bound()) {
++num_vars_bound_to_v;
} else {
tmp_sum.push_back(MakeIsEqualCstVar(vars[i], value));
}
}
}
return MakeSumEquality(tmp_sum,
MakeSum(max_count, -num_vars_bound_to_v)->Var());
}
}
// ---------- Distribute ----------
namespace {
class AtMost : public Constraint {
public:
AtMost(Solver* const s, std::vector<IntVar*> vars, int64_t value,
int64_t max_count)
: Constraint(s),
vars_(std::move(vars)),
value_(value),
max_count_(max_count),
current_count_(0) {}
~AtMost() override {}
void Post() override {
for (IntVar* var : vars_) {
if (!var->Bound() && var->Contains(value_)) {
Demon* const d = MakeConstraintDemon1(solver(), this, &AtMost::OneBound,
"OneBound", var);
var->WhenBound(d);
}
}
}
void InitialPropagate() override {
for (IntVar* var : vars_) {
if (var->Bound() && var->Min() == value_) {
current_count_.Incr(solver());
}
}
CheckCount();
}
void OneBound(IntVar* var) {
if (var->Min() == value_) {
current_count_.Incr(solver());
CheckCount();
}
}
void CheckCount() {
if (current_count_.Value() < max_count_) {
return;
}
// Remove all remaining values.
int forced = 0;
for (IntVar* var : vars_) {
if (var->Bound()) {
if (var->Min() == value_) {
forced++;
}
} else {
var->RemoveValue(value_);
}
}
if (forced > max_count_) {
solver()->Fail();
}
}
std::string DebugString() const override {
return absl::StrFormat("AtMost(%s, %d, %d)",
JoinDebugStringPtr(vars_, ", "), value_, max_count_);
}
void Accept(ModelVisitor* const visitor) const override {
visitor->BeginVisitConstraint(ModelVisitor::kAtMost, this);
visitor->VisitIntegerVariableArrayArgument(ModelVisitor::kVarsArgument,
vars_);
visitor->VisitIntegerArgument(ModelVisitor::kValueArgument, value_);
visitor->VisitIntegerArgument(ModelVisitor::kCountArgument, max_count_);
visitor->EndVisitConstraint(ModelVisitor::kAtMost, this);
}
private:
const std::vector<IntVar*> vars_;
const int64_t value_;
const int64_t max_count_;
NumericalRev<int> current_count_;
};
class Distribute : public Constraint {
public:
Distribute(Solver* const s, const std::vector<IntVar*>& vars,
const std::vector<int64_t>& values,
const std::vector<IntVar*>& cards)
: Constraint(s),
vars_(vars),
values_(values),
cards_(cards),
undecided_(vars.size(), cards.size()),
min_(cards.size(), 0),
max_(cards.size(), 0) {}
~Distribute() override {}
void Post() override;
void InitialPropagate() override;
void OneBound(int index);
void OneDomain(int index);
void CountVar(int cindex);
void CardMin(int cindex);
void CardMax(int cindex);
std::string DebugString() const override {
return absl::StrFormat(
"Distribute(vars = [%s], values = [%s], cards = [%s])",
JoinDebugStringPtr(vars_, ", "), absl::StrJoin(values_, ", "),
JoinDebugStringPtr(cards_, ", "));
}
void Accept(ModelVisitor* const visitor) const override {
visitor->BeginVisitConstraint(ModelVisitor::kDistribute, this);
visitor->VisitIntegerVariableArrayArgument(ModelVisitor::kVarsArgument,
vars_);
visitor->VisitIntegerArrayArgument(ModelVisitor::kValuesArgument, values_);
visitor->VisitIntegerVariableArrayArgument(ModelVisitor::kCardsArgument,
cards_);
visitor->EndVisitConstraint(ModelVisitor::kDistribute, this);
}
private:
int64_t var_size() const { return vars_.size(); }
int64_t card_size() const { return cards_.size(); }
const std::vector<IntVar*> vars_;
const std::vector<int64_t> values_;
const std::vector<IntVar*> cards_;
RevBitMatrix undecided_;
NumericalRevArray<int> min_;
NumericalRevArray<int> max_;
};
void Distribute::Post() {
for (int i = 0; i < var_size(); ++i) {
IntVar* const var = vars_[i];
if (!var->Bound()) {
Demon* d = MakeConstraintDemon1(solver(), this, &Distribute::OneBound,
"OneBound", i);
var->WhenBound(d);
d = MakeConstraintDemon1(solver(), this, &Distribute::OneDomain,
"OneDomain", i);
var->WhenDomain(d);
}
}
for (int i = 0; i < card_size(); ++i) {
if (!cards_[i]->Bound()) {
Demon* d =
MakeConstraintDemon1(solver(), this, &Distribute::CountVar, "Var", i);
cards_[i]->WhenRange(d);
}
}
}
void Distribute::InitialPropagate() {
Solver* const s = solver();
for (int j = 0; j < card_size(); ++j) {
int min = 0;
int max = 0;
for (int i = 0; i < var_size(); ++i) {
IntVar* const var = vars_[i];
if (var->Bound()) {
if (var->Min() == values_[j]) {
min++;
max++;
}
} else {
if (var->Contains(values_[j])) {
max++;
undecided_.SetToOne(s, i, j);
}
}
}
cards_[j]->SetRange(min, max);
if (cards_[j]->Max() == min) {
CardMin(j);
} else if (cards_[j]->Min() == max) {
CardMax(j);
}
min_.SetValue(s, j, min);
max_.SetValue(s, j, max);
}
}
void Distribute::OneBound(int index) {
IntVar* const var = vars_[index];
Solver* const s = solver();
for (int j = 0; j < card_size(); ++j) {
if (undecided_.IsSet(index, j)) {
undecided_.SetToZero(s, index, j);
if (var->Min() == values_[j]) {
min_.Incr(s, j);
cards_[j]->SetMin(min_[j]);
if (min_[j] == cards_[j]->Max()) {
CardMin(j);
}
} else {
max_.Decr(s, j);
cards_[j]->SetMax(max_[j]);
if (max_[j] == cards_[j]->Min()) {
CardMax(j);
}
}
}
}
}
void Distribute::OneDomain(int index) {
IntVar* const var = vars_[index];
Solver* const s = solver();
for (int j = 0; j < card_size(); ++j) {
if (undecided_.IsSet(index, j)) {
if (!var->Contains(values_[j])) {
undecided_.SetToZero(s, index, j);
max_.Decr(s, j);
cards_[j]->SetMax(max_[j]);
if (max_[j] == cards_[j]->Min()) {
CardMax(j);
}
}
}
}
}
void Distribute::CountVar(int cindex) {
if (cards_[cindex]->Min() > max_[cindex] ||
cards_[cindex]->Max() < min_[cindex]) {
solver()->Fail();
}
if (cards_[cindex]->Min() == max_[cindex]) {
CardMax(cindex);
}
if (cards_[cindex]->Max() == min_[cindex]) {
CardMin(cindex);
}
}
void Distribute::CardMin(int cindex) {
for (int i = 0; i < var_size(); ++i) {
if (undecided_.IsSet(i, cindex)) {
vars_[i]->RemoveValue(values_[cindex]);
}
}
}
void Distribute::CardMax(int cindex) {
for (int i = 0; i < var_size(); ++i) {
if (undecided_.IsSet(i, cindex)) {
vars_[i]->SetValue(values_[cindex]);
}
}
}
// ----- FastDistribute -----
class FastDistribute : public Constraint {
public:
FastDistribute(Solver* const s, const std::vector<IntVar*>& vars,
const std::vector<IntVar*>& cards);
~FastDistribute() override {}
void Post() override;
void InitialPropagate() override;
void OneBound(int index);
void OneDomain(int index);
void CountVar(int card_index);
void CardMin(int card_index);
void CardMax(int card_index);
std::string DebugString() const override;
void SetRevCannotContribute(int64_t var_index, int64_t card_index) {
Solver* const s = solver();
undecided_.SetToZero(s, var_index, card_index);
max_.Decr(s, card_index);
cards_[card_index]->SetMax(max_[card_index]);
if (max_[card_index] == cards_[card_index]->Min()) {
CardMax(card_index);
}
}
void SetRevDoContribute(int64_t var_index, int64_t card_index) {
Solver* const s = solver();
undecided_.SetToZero(s, var_index, card_index);
min_.Incr(s, card_index);
cards_[card_index]->SetMin(min_[card_index]);
if (min_[card_index] == cards_[card_index]->Max()) {
CardMin(card_index);
}
}
void Accept(ModelVisitor* const visitor) const override {
visitor->BeginVisitConstraint(ModelVisitor::kDistribute, this);
visitor->VisitIntegerVariableArrayArgument(ModelVisitor::kVarsArgument,
vars_);
visitor->VisitIntegerVariableArrayArgument(ModelVisitor::kCardsArgument,
cards_);
visitor->EndVisitConstraint(ModelVisitor::kDistribute, this);
}
private:
int64_t var_size() const { return vars_.size(); }
int64_t card_size() const { return cards_.size(); }
const std::vector<IntVar*> vars_;
const std::vector<IntVar*> cards_;
RevBitMatrix undecided_;
NumericalRevArray<int> min_;
NumericalRevArray<int> max_;
std::vector<IntVarIterator*> holes_;
};
FastDistribute::FastDistribute(Solver* const s,
const std::vector<IntVar*>& vars,
const std::vector<IntVar*>& cards)
: Constraint(s),
vars_(vars),
cards_(cards),
undecided_(vars.size(), cards.size()),
min_(cards.size(), 0),
max_(cards.size(), 0),
holes_(vars.size()) {
for (int var_index = 0; var_index < var_size(); ++var_index) {
holes_[var_index] = vars_[var_index]->MakeHoleIterator(true);
}
}
std::string FastDistribute::DebugString() const {
return absl::StrFormat("FastDistribute(vars = [%s], cards = [%s])",
JoinDebugStringPtr(vars_, ", "),
JoinDebugStringPtr(cards_, ", "));
}
void FastDistribute::Post() {
for (int var_index = 0; var_index < var_size(); ++var_index) {
IntVar* const var = vars_[var_index];
if (!var->Bound()) {
Demon* d = MakeConstraintDemon1(solver(), this, &FastDistribute::OneBound,
"OneBound", var_index);
var->WhenBound(d);
d = MakeConstraintDemon1(solver(), this, &FastDistribute::OneDomain,
"OneDomain", var_index);
var->WhenDomain(d);
}
}
for (int card_index = 0; card_index < card_size(); ++card_index) {
if (!cards_[card_index]->Bound()) {
Demon* d = MakeConstraintDemon1(solver(), this, &FastDistribute::CountVar,
"Var", card_index);
cards_[card_index]->WhenRange(d);
}
}
}
void FastDistribute::InitialPropagate() {
Solver* const s = solver();
for (int card_index = 0; card_index < card_size(); ++card_index) {
int min = 0;
int max = 0;
for (int var_index = 0; var_index < var_size(); ++var_index) {
IntVar* const var = vars_[var_index];
if (var->Bound() && var->Min() == card_index) {
min++;
max++;
} else if (var->Contains(card_index)) {
max++;
undecided_.SetToOne(s, var_index, card_index);
}
}
min_.SetValue(s, card_index, min);
max_.SetValue(s, card_index, max);
CountVar(card_index);
}
}
void FastDistribute::OneBound(int index) {
IntVar* const var = vars_[index];
for (int card_index = 0; card_index < card_size(); ++card_index) {
if (undecided_.IsSet(index, card_index)) {
if (var->Min() == card_index) {
SetRevDoContribute(index, card_index);
} else {
SetRevCannotContribute(index, card_index);
}
}
}
}
void FastDistribute::OneDomain(int index) {
IntVar* const var = vars_[index];
const int64_t oldmin = var->OldMin();
const int64_t oldmax = var->OldMax();
const int64_t vmin = var->Min();
const int64_t vmax = var->Max();
for (int64_t card_index = std::max(oldmin, int64_t{0});
card_index < std::min(vmin, card_size()); ++card_index) {
if (undecided_.IsSet(index, card_index)) {
SetRevCannotContribute(index, card_index);
}
}
for (const int64_t card_index : InitAndGetValues(holes_[index])) {
if (card_index >= 0 && card_index < card_size() &&
undecided_.IsSet(index, card_index)) {
SetRevCannotContribute(index, card_index);
}
}
for (int64_t card_index = std::max(vmax + 1, int64_t{0});
card_index <= std::min(oldmax, card_size() - 1); ++card_index) {
if (undecided_.IsSet(index, card_index)) {
SetRevCannotContribute(index, card_index);
}
}
}
void FastDistribute::CountVar(int card_index) {
const int64_t stored_min = min_[card_index];
const int64_t stored_max = max_[card_index];
cards_[card_index]->SetRange(min_[card_index], max_[card_index]);
if (cards_[card_index]->Min() == stored_max) {
CardMax(card_index);
}
if (cards_[card_index]->Max() == stored_min) {
CardMin(card_index);
}
}
void FastDistribute::CardMin(int card_index) {
for (int var_index = 0; var_index < var_size(); ++var_index) {
if (undecided_.IsSet(var_index, card_index)) {
vars_[var_index]->RemoveValue(card_index);
}
}
}
void FastDistribute::CardMax(int card_index) {
for (int var_index = 0; var_index < var_size(); ++var_index) {
if (undecided_.IsSet(var_index, card_index)) {
vars_[var_index]->SetValue(card_index);
}
}
}
// ----- BoundedDistribute -----
class BoundedDistribute : public Constraint {
public:
BoundedDistribute(Solver* const s, const std::vector<IntVar*>& vars,
const std::vector<int64_t>& values,
const std::vector<int64_t>& card_min,
const std::vector<int64_t>& card_max);
~BoundedDistribute() override {}
void Post() override;
void InitialPropagate() override;
void OneBound(int index);
void OneDomain(int index);
void CountVar(int card_index);
void CardMin(int card_index);
void CardMax(int card_index);
std::string DebugString() const override;
void SetRevCannotContribute(int64_t var_index, int64_t card_index) {
Solver* const s = solver();
undecided_.SetToZero(s, var_index, card_index);
max_.Decr(s, card_index);
if (max_[card_index] < card_min_[card_index]) {
solver()->Fail();
}
if (max_[card_index] == card_min_[card_index]) {
CardMax(card_index);
}
}
void SetRevDoContribute(int64_t var_index, int64_t card_index) {
Solver* const s = solver();
undecided_.SetToZero(s, var_index, card_index);
min_.Incr(s, card_index);
if (min_[card_index] > card_max_[card_index]) {
solver()->Fail();
}
if (min_[card_index] == card_max_[card_index]) {
CardMin(card_index);
}
}
void Accept(ModelVisitor* const visitor) const override {
visitor->BeginVisitConstraint(ModelVisitor::kDistribute, this);
visitor->VisitIntegerVariableArrayArgument(ModelVisitor::kVarsArgument,
vars_);
visitor->VisitIntegerArrayArgument(ModelVisitor::kValuesArgument, values_);
visitor->VisitIntegerArrayArgument(ModelVisitor::kMinArgument, card_min_);
visitor->VisitIntegerArrayArgument(ModelVisitor::kMaxArgument, card_max_);
visitor->EndVisitConstraint(ModelVisitor::kDistribute, this);
}
private:
int64_t var_size() const { return vars_.size(); }
int64_t card_size() const { return values_.size(); }
const std::vector<IntVar*> vars_;
const std::vector<int64_t> values_;
const std::vector<int64_t> card_min_;
const std::vector<int64_t> card_max_;
RevBitMatrix undecided_;
NumericalRevArray<int> min_;
NumericalRevArray<int> max_;
std::vector<IntVarIterator*> holes_;
};
BoundedDistribute::BoundedDistribute(Solver* const s,
const std::vector<IntVar*>& vars,
const std::vector<int64_t>& values,
const std::vector<int64_t>& card_min,
const std::vector<int64_t>& card_max)
: Constraint(s),
vars_(vars),
values_(values),
card_min_(card_min),
card_max_(card_max),
undecided_(vars.size(), values.size()),
min_(values.size(), 0),
max_(values.size(), 0),
holes_(vars.size()) {
for (int var_index = 0; var_index < var_size(); ++var_index) {
holes_[var_index] = vars_[var_index]->MakeHoleIterator(true);
}
}
std::string BoundedDistribute::DebugString() const {
return absl::StrFormat(
"BoundedDistribute([%s], values = [%s], card_min = [%s], card_max = "
"[%s]",
JoinDebugStringPtr(vars_, ", "), absl::StrJoin(values_, ", "),
absl::StrJoin(card_min_, ", "), absl::StrJoin(card_max_, ", "));
}
void BoundedDistribute::Post() {
for (int var_index = 0; var_index < var_size(); ++var_index) {
IntVar* const var = vars_[var_index];
if (!var->Bound()) {
Demon* d = MakeConstraintDemon1(
solver(), this, &BoundedDistribute::OneBound, "OneBound", var_index);
var->WhenBound(d);
d = MakeConstraintDemon1(solver(), this, &BoundedDistribute::OneDomain,
"OneDomain", var_index);
var->WhenDomain(d);
}
}
}
void BoundedDistribute::InitialPropagate() {
Solver* const s = solver();
int64_t sum_card_min = 0;
for (int i = 0; i < card_size(); ++i) {
if (card_max_[i] < card_min_[i]) {
solver()->Fail();
}
sum_card_min += card_min_[i];
}
if (sum_card_min > var_size()) {
s->Fail();
}
if (sum_card_min == var_size()) {
for (int i = 0; i < var_size(); ++i) {
vars_[i]->SetValues(values_);
}
}
for (int card_index = 0; card_index < card_size(); ++card_index) {
const int64_t value = values_[card_index];
int min = 0;
int max = 0;
for (int i = 0; i < var_size(); ++i) {
IntVar* const var = vars_[i];
if (var->Bound()) {
if (var->Min() == value) {
min++;
max++;
}
} else if (var->Contains(value)) {
max++;
undecided_.SetToOne(s, i, card_index);
}
}
min_.SetValue(s, card_index, min);
max_.SetValue(s, card_index, max);
CountVar(card_index);
}
}
void BoundedDistribute::OneBound(int index) {
IntVar* const var = vars_[index];
const int64_t var_min = var->Min();
for (int card_index = 0; card_index < card_size(); ++card_index) {
if (undecided_.IsSet(index, card_index)) {
if (var_min == values_[card_index]) {
SetRevDoContribute(index, card_index);
} else {
SetRevCannotContribute(index, card_index);
}
}
}
}
void BoundedDistribute::OneDomain(int index) {
IntVar* const var = vars_[index];
for (int card_index = 0; card_index < card_size(); ++card_index) {
if (undecided_.IsSet(index, card_index)) {
if (!var->Contains(values_[card_index])) {
SetRevCannotContribute(index, card_index);
}
}
}
}
void BoundedDistribute::CountVar(int card_index) {
const int64_t stored_min = min_[card_index];
const int64_t stored_max = max_[card_index];
if (card_min_[card_index] > stored_max ||
card_max_[card_index] < stored_min) {
solver()->Fail();
}
if (card_min_[card_index] == stored_max) {
CardMax(card_index);
}
if (card_max_[card_index] == stored_min) {
CardMin(card_index);
}
}
void BoundedDistribute::CardMin(int card_index) {
for (int var_index = 0; var_index < var_size(); ++var_index) {
if (undecided_.IsSet(var_index, card_index)) {
vars_[var_index]->RemoveValue(values_[card_index]);
}
}
}
void BoundedDistribute::CardMax(int card_index) {
for (int var_index = 0; var_index < var_size(); ++var_index) {
if (undecided_.IsSet(var_index, card_index)) {
vars_[var_index]->SetValue(values_[card_index]);
}
}
}
// ----- BoundedFastDistribute -----
class BoundedFastDistribute : public Constraint {
public:
BoundedFastDistribute(Solver* const s, const std::vector<IntVar*>& vars,
const std::vector<int64_t>& card_min,
const std::vector<int64_t>& card_max);
~BoundedFastDistribute() override {}
void Post() override;
void InitialPropagate() override;
void OneBound(int index);
void OneDomain(int index);
void CountVar(int card_index);
void CardMin(int card_index);
void CardMax(int card_index);
std::string DebugString() const override;
void SetRevCannotContribute(int64_t var_index, int64_t card_index) {
Solver* const s = solver();
undecided_.SetToZero(s, var_index, card_index);
max_.Decr(s, card_index);
if (max_[card_index] < card_min_[card_index]) {
solver()->Fail();
}
if (max_[card_index] == card_min_[card_index]) {
CardMax(card_index);
}
}
void SetRevDoContribute(int64_t var_index, int64_t card_index) {
Solver* const s = solver();
undecided_.SetToZero(s, var_index, card_index);
min_.Incr(s, card_index);
if (min_[card_index] > card_max_[card_index]) {
solver()->Fail();
}
if (min_[card_index] == card_max_[card_index]) {
CardMin(card_index);
}
}
void Accept(ModelVisitor* const visitor) const override {
visitor->BeginVisitConstraint(ModelVisitor::kDistribute, this);
visitor->VisitIntegerVariableArrayArgument(ModelVisitor::kVarsArgument,
vars_);
visitor->VisitIntegerArrayArgument(ModelVisitor::kMinArgument, card_min_);
visitor->VisitIntegerArrayArgument(ModelVisitor::kMaxArgument, card_max_);
visitor->EndVisitConstraint(ModelVisitor::kDistribute, this);
}
private:
int64_t var_size() const { return vars_.size(); }
int64_t card_size() const { return card_min_.size(); }
const std::vector<IntVar*> vars_;
const std::vector<int64_t> card_min_;
const std::vector<int64_t> card_max_;
RevBitMatrix undecided_;
NumericalRevArray<int> min_;
NumericalRevArray<int> max_;
std::vector<IntVarIterator*> holes_;
};
BoundedFastDistribute::BoundedFastDistribute(
Solver* const s, const std::vector<IntVar*>& vars,
const std::vector<int64_t>& card_min, const std::vector<int64_t>& card_max)
: Constraint(s),
vars_(vars),
card_min_(card_min),
card_max_(card_max),
undecided_(vars.size(), card_min.size()),
min_(card_min.size(), 0),
max_(card_max.size(), 0),
holes_(vars.size()) {
for (int var_index = 0; var_index < var_size(); ++var_index) {
holes_[var_index] = vars_[var_index]->MakeHoleIterator(true);
}
}
std::string BoundedFastDistribute::DebugString() const {
return absl::StrFormat(
"BoundedFastDistribute([%s], card_min = [%s], card_max = [%s]",
JoinDebugStringPtr(vars_, ", "), absl::StrJoin(card_min_, ", "),
absl::StrJoin(card_max_, ", "));
}
void BoundedFastDistribute::Post() {
for (int var_index = 0; var_index < var_size(); ++var_index) {
IntVar* const var = vars_[var_index];
if (!var->Bound()) {
Demon* d =
MakeConstraintDemon1(solver(), this, &BoundedFastDistribute::OneBound,
"OneBound", var_index);
var->WhenBound(d);
d = MakeConstraintDemon1(solver(), this,
&BoundedFastDistribute::OneDomain, "OneDomain",
var_index);
var->WhenDomain(d);
}
}
}
void BoundedFastDistribute::InitialPropagate() {
Solver* const s = solver();
int64_t sum_card_min = 0;
for (int i = 0; i < card_size(); ++i) {
if (card_max_[i] < card_min_[i]) {
solver()->Fail();
}
sum_card_min += card_min_[i];
}
if (sum_card_min > var_size()) {
s->Fail();
}
if (sum_card_min == var_size()) {
for (int i = 0; i < var_size(); ++i) {
vars_[i]->SetRange(0, card_size() - 1);
}
}
for (int card_index = 0; card_index < card_size(); ++card_index) {
int min = 0;
int max = 0;
for (int i = 0; i < var_size(); ++i) {
IntVar* const var = vars_[i];
if (var->Bound()) {
if (var->Min() == card_index) {
min++;
max++;
}
} else if (var->Contains(card_index)) {
max++;
undecided_.SetToOne(s, i, card_index);
}
}
min_.SetValue(s, card_index, min);
max_.SetValue(s, card_index, max);
CountVar(card_index);
}
}
void BoundedFastDistribute::OneBound(int index) {
IntVar* const var = vars_[index];
const int64_t var_min = var->Min();
for (int card_index = 0; card_index < card_size(); ++card_index) {
if (undecided_.IsSet(index, card_index)) {
if (var_min == card_index) {
SetRevDoContribute(index, card_index);
} else {
SetRevCannotContribute(index, card_index);
}
}
}
}
void BoundedFastDistribute::OneDomain(int index) {
IntVar* const var = vars_[index];
const int64_t oldmin = var->OldMin();
const int64_t oldmax = var->OldMax();
const int64_t vmin = var->Min();
const int64_t vmax = var->Max();
for (int64_t card_index = std::max(oldmin, int64_t{0});
card_index < std::min(vmin, card_size()); ++card_index) {
if (undecided_.IsSet(index, card_index)) {
SetRevCannotContribute(index, card_index);
}
}
for (const int64_t card_index : InitAndGetValues(holes_[index])) {
if (card_index >= 0 && card_index < card_size() &&
undecided_.IsSet(index, card_index)) {
SetRevCannotContribute(index, card_index);
}
}
for (int64_t card_index = std::max(vmax + 1, int64_t{0});
card_index <= std::min(oldmax, card_size() - 1); ++card_index) {
if (undecided_.IsSet(index, card_index)) {
SetRevCannotContribute(index, card_index);
}
}
}
void BoundedFastDistribute::CountVar(int card_index) {
const int64_t stored_min = min_[card_index];
const int64_t stored_max = max_[card_index];
if (card_min_[card_index] > stored_max ||
card_max_[card_index] < stored_min) {
solver()->Fail();
}
if (card_min_[card_index] == stored_max) {
CardMax(card_index);
}
if (card_max_[card_index] == stored_min) {
CardMin(card_index);
}
}
void BoundedFastDistribute::CardMin(int card_index) {
for (int var_index = 0; var_index < var_size(); ++var_index) {
if (undecided_.IsSet(var_index, card_index)) {
vars_[var_index]->RemoveValue(card_index);
}
}
}
void BoundedFastDistribute::CardMax(int card_index) {
for (int var_index = 0; var_index < var_size(); ++var_index) {
if (undecided_.IsSet(var_index, card_index)) {
vars_[var_index]->SetValue(card_index);
}
}
}
// ----- SetAllToZero -----
class SetAllToZero : public Constraint {
public:
SetAllToZero(Solver* const s, const std::vector<IntVar*>& vars)
: Constraint(s), vars_(vars) {}
~SetAllToZero() override {}
void Post() override {}
void InitialPropagate() override {
for (int i = 0; i < vars_.size(); ++i) {
vars_[i]->SetValue(0);
}
}
std::string DebugString() const override { return "SetAllToZero()"; }
void Accept(ModelVisitor* const visitor) const override {
visitor->BeginVisitConstraint(ModelVisitor::kDistribute, this);
visitor->VisitIntegerVariableArrayArgument(ModelVisitor::kCardsArgument,
vars_);
visitor->EndVisitConstraint(ModelVisitor::kDistribute, this);
}
private:
const std::vector<IntVar*> vars_;
};
} // namespace
// ----- Factory -----
Constraint* Solver::MakeAtMost(std::vector<IntVar*> vars, int64_t value,
int64_t max_count) {
CHECK_GE(max_count, 0);
if (max_count >= vars.size()) {
return MakeTrueConstraint();
}
return RevAlloc(new AtMost(this, std::move(vars), value, max_count));
}
Constraint* Solver::MakeDistribute(const std::vector<IntVar*>& vars,
const std::vector<int64_t>& values,
const std::vector<IntVar*>& cards) {
if (vars.empty()) {
return RevAlloc(new SetAllToZero(this, cards));
}
CHECK_EQ(values.size(), cards.size());
for (IntVar* const var : vars) {
CHECK_EQ(this, var->solver());
}
// TODO(user) : we can sort values (and cards) before doing the test.
bool fast = true;
for (int i = 0; i < values.size(); ++i) {
if (values[i] != i) {
fast = false;
break;
}
}
for (IntVar* const card : cards) {
CHECK_EQ(this, card->solver());
}
if (fast) {
return RevAlloc(new FastDistribute(this, vars, cards));
} else {
return RevAlloc(new Distribute(this, vars, values, cards));
}
}
Constraint* Solver::MakeDistribute(const std::vector<IntVar*>& vars,
const std::vector<int>& values,
const std::vector<IntVar*>& cards) {
return MakeDistribute(vars, ToInt64Vector(values), cards);
}