69 lines
2.0 KiB
Go
69 lines
2.0 KiB
Go
// 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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// The assumptions_sample_sat command is an example of setting assumptions on a model.
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package main
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import (
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"fmt"
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log "github.com/golang/glog"
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"github.com/google/or-tools/ortools/sat/go/cpmodel"
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cmpb "github.com/google/or-tools/ortools/sat/proto/cpmodel"
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)
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func assumptionsSampleSat() error {
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model := cpmodel.NewCpModelBuilder()
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domain := cpmodel.NewDomain(0, 10)
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x := model.NewIntVarFromDomain(domain).WithName("x")
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y := model.NewIntVarFromDomain(domain).WithName("y")
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z := model.NewIntVarFromDomain(domain).WithName("z")
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a := model.NewBoolVar().WithName("a")
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b := model.NewBoolVar().WithName("b")
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c := model.NewBoolVar().WithName("c")
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model.AddGreaterThan(x, y).OnlyEnforceIf(a)
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model.AddGreaterThan(y, z).OnlyEnforceIf(b)
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model.AddGreaterThan(z, x).OnlyEnforceIf(c)
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// Add assumptions
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model.AddAssumption(a, b, c)
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m, err := model.Model()
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if err != nil {
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return fmt.Errorf("failed to instantiate the CP model: %w", err)
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}
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response, err := cpmodel.SolveCpModel(m)
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if err != nil {
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return fmt.Errorf("failed to solve the model: %w", err)
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}
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fmt.Printf("status: %s\n", response.GetStatus())
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if response.GetStatus() == cmpb.CpSolverStatus_INFEASIBLE {
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fmt.Println("sufficient assumptions for infeasibility:")
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for _, index := range response.GetSufficientAssumptionsForInfeasibility() {
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fmt.Printf("%d\n", index)
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}
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}
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return nil
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}
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func main() {
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if err := assumptionsSampleSat(); err != nil {
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log.Exitf("assumptionsSampleSat returned with error: %v", err)
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}
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}
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