122 lines
4.1 KiB
C++
122 lines
4.1 KiB
C++
// Copyright 2010 Google
|
|
// 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.
|
|
|
|
#include "base/commandlineflags.h"
|
|
#include "base/integral_types.h"
|
|
#include "base/logging.h"
|
|
#include "base/scoped_ptr.h"
|
|
#include "base/stringprintf.h"
|
|
#include "constraint_solver/constraint_solveri.h"
|
|
#include "examples/global_arith.h"
|
|
|
|
DEFINE_int32(size, 20, "Size of the problem");
|
|
|
|
namespace operations_research {
|
|
// ---------- Examples ----------
|
|
|
|
void DeepSearchTreeArith(int size) {
|
|
LOG(INFO) << "DeepSearchTreeArith: size = " << size;
|
|
const int64 rmax = 1 << size;
|
|
|
|
Solver solver("DeepSearchTreeArith");
|
|
IntVar* const v1 = solver.MakeIntVar(1, rmax, "v1");
|
|
IntVar* const v2 = solver.MakeIntVar(0, rmax, "v2");
|
|
IntVar* const v3 = solver.MakeIntVar(0, rmax, "v3");
|
|
|
|
GlobalArithmeticConstraint* const global =
|
|
solver.RevAlloc(new GlobalArithmeticConstraint(&solver));
|
|
|
|
|
|
global->Add(global->MakeVarEqualVarPlusOffset(v1, v2, 0));
|
|
global->Add(global->MakeVarEqualVarPlusOffset(v2, v3, 0));
|
|
const int left =
|
|
global->MakeRowConstraint(0, v1, -1, v2, -1, v3, 1, kint64max);
|
|
const int right =
|
|
global->MakeRowConstraint(0, v1, -1, v2, 1, v3, -1, kint64max);
|
|
global->Add(global->MakeOrConstraint(left, right));
|
|
|
|
global->Post();
|
|
}
|
|
|
|
void SlowPropagationArith(int size) {
|
|
LOG(INFO) << "SlowPropagationArith: size = " << size;
|
|
const int64 rmin = -(1 << size);
|
|
const int64 rmax = 1 << size;
|
|
|
|
Solver solver("SlowPropagationArith");
|
|
IntVar* const v1 = solver.MakeIntVar(rmin, rmax, "v1");
|
|
IntVar* const v2 = solver.MakeIntVar(rmin, rmax, "v2");
|
|
|
|
GlobalArithmeticConstraint* const global =
|
|
solver.RevAlloc(new GlobalArithmeticConstraint(&solver));
|
|
|
|
global->Add(global->MakeRowConstraint(1, v1, 1, v2, -1, kint64max));
|
|
global->Add(global->MakeRowConstraint(0, v1, -1, v2, 1, kint64max));
|
|
|
|
global->Post();
|
|
}
|
|
|
|
void DeepSearchTree(int size){
|
|
LOG(INFO) << "DeepSearchTree: size = " << size;
|
|
Solver s("DeepSearchTree");
|
|
const int64 rmax = 1 << size;
|
|
IntVar* const i = s.MakeIntVar(1, rmax, "i");
|
|
IntVar* const j = s.MakeIntVar(0, rmax, "j");
|
|
IntVar* const k = s.MakeIntVar(0, rmax, "k");
|
|
|
|
s.AddConstraint(s.MakeEquality(i, j));
|
|
s.AddConstraint(s.MakeEquality(j, k));
|
|
IntVar* const left = s.MakeIsLessOrEqualVar(s.MakeSum(i, j), k);
|
|
IntVar* const right = s.MakeIsLessOrEqualVar(s.MakeSum(i, k), j);
|
|
|
|
s.AddConstraint(s.MakeGreater(s.MakeSum(left, right), Zero()));
|
|
|
|
// search decision
|
|
DecisionBuilder* const db = s.MakePhase(i, j, k,
|
|
Solver::CHOOSE_FIRST_UNBOUND,
|
|
Solver::ASSIGN_MIN_VALUE);
|
|
SearchMonitor* const log = s.MakeSearchLog(100000);
|
|
|
|
s.Solve(db, log); // go!
|
|
}
|
|
|
|
|
|
void SlowPropagation(int size) {
|
|
LOG(INFO) << "SlowPropagation: size = " << size;
|
|
Solver s("SlowPropagation");
|
|
const int64 rmin = -(1 << size);
|
|
const int64 rmax = 1 << size;
|
|
IntVar* const i = s.MakeIntVar(rmin, rmax, "i");
|
|
IntVar* const j = s.MakeIntVar(rmin, rmax, "j");
|
|
s.AddConstraint(s.MakeGreater(i, j));
|
|
s.AddConstraint(s.MakeLessOrEqual(i, j));
|
|
|
|
DecisionBuilder* const db = s.MakePhase(i, j,
|
|
Solver::CHOOSE_FIRST_UNBOUND,
|
|
Solver::ASSIGN_MIN_VALUE);
|
|
|
|
SearchMonitor* const log = s.MakeSearchLog(100000);
|
|
|
|
s.Solve(db, log);
|
|
}
|
|
} // namespace operations_research
|
|
|
|
int main(int argc, char **argv) {
|
|
google::ParseCommandLineFlags(&argc, &argv, true);
|
|
operations_research::DeepSearchTreeArith(FLAGS_size);
|
|
operations_research::SlowPropagationArith(FLAGS_size);
|
|
// operations_research::DeepSearchTree(FLAGS_size);
|
|
// operations_research::SlowPropagation(FLAGS_size);
|
|
return 0;
|
|
}
|