78 lines
2.4 KiB
C++
78 lines
2.4 KiB
C++
// Copyright 2010-2025 Google LLC
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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// [START program]
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#include <stdlib.h>
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#include "absl/base/log_severity.h"
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#include "absl/log/globals.h"
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#include "ortools/base/init_google.h"
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#include "ortools/base/logging.h"
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#include "ortools/sat/cp_model.h"
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#include "ortools/sat/cp_model.pb.h"
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#include "ortools/sat/cp_model_solver.h"
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#include "ortools/util/sorted_interval_list.h"
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namespace operations_research {
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namespace sat {
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void CloneModelSampleSat() {
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// [START model]
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CpModelBuilder cp_model;
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// [END model]
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// [START variables]
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const Domain domain(0, 2);
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const IntVar x = cp_model.NewIntVar(domain).WithName("x");
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const IntVar y = cp_model.NewIntVar(domain).WithName("y");
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const IntVar z = cp_model.NewIntVar(domain).WithName("z");
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// [END variables]
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// [START constraints]
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cp_model.AddNotEqual(x, y);
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// [END constraints]
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// [START objective]
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cp_model.Maximize(x + 2 * y + 3 * z);
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// [END objective]
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const CpSolverResponse initial_response = Solve(cp_model.Build());
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LOG(INFO) << "Optimal value of the original model: "
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<< initial_response.objective_value();
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// [START clone]
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CpModelBuilder copy = cp_model.Clone();
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// Add new constraint: copy_of_x + copy_of_y == 1.
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IntVar copy_of_x = copy.GetIntVarFromProtoIndex(x.index());
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IntVar copy_of_y = copy.GetIntVarFromProtoIndex(y.index());
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copy.AddLessOrEqual(copy_of_x + copy_of_y, 1);
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// [END clone]
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const CpSolverResponse modified_response = Solve(copy.Build());
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LOG(INFO) << "Optimal value of the modified model: "
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<< modified_response.objective_value();
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}
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} // namespace sat
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} // namespace operations_research
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int main(int argc, char* argv[]) {
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InitGoogle(argv[0], &argc, &argv, true);
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absl::SetStderrThreshold(absl::LogSeverityAtLeast::kInfo);
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operations_research::sat::CloneModelSampleSat();
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return EXIT_SUCCESS;
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}
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// [END program]
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