c34026b101
note: done using ```sh git grep -l "2010-2024 Google" | xargs sed -i 's/2010-2024 Google/2010-2025 Google/' ```
95 lines
3.3 KiB
Java
95 lines
3.3 KiB
Java
// 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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// Minimal example to call the MIP solver.
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// [START program]
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package com.google.ortools.linearsolver.samples;
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// [START import]
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import com.google.ortools.Loader;
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import com.google.ortools.linearsolver.MPConstraint;
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import com.google.ortools.linearsolver.MPObjective;
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import com.google.ortools.linearsolver.MPSolver;
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import com.google.ortools.linearsolver.MPVariable;
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// [END import]
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/** Minimal Mixed Integer Programming example to showcase calling the solver. */
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public final class SimpleMipProgram {
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public static void main(String[] args) {
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Loader.loadNativeLibraries();
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// [START solver]
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// Create the linear solver with the SCIP backend.
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MPSolver solver = MPSolver.createSolver("SCIP");
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if (solver == null) {
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System.out.println("Could not create solver SCIP");
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return;
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}
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// [END solver]
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// [START variables]
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double infinity = java.lang.Double.POSITIVE_INFINITY;
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// x and y are integer non-negative variables.
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MPVariable x = solver.makeIntVar(0.0, infinity, "x");
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MPVariable y = solver.makeIntVar(0.0, infinity, "y");
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System.out.println("Number of variables = " + solver.numVariables());
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// [END variables]
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// [START constraints]
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// x + 7 * y <= 17.5.
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MPConstraint c0 = solver.makeConstraint(-infinity, 17.5, "c0");
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c0.setCoefficient(x, 1);
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c0.setCoefficient(y, 7);
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// x <= 3.5.
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MPConstraint c1 = solver.makeConstraint(-infinity, 3.5, "c1");
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c1.setCoefficient(x, 1);
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c1.setCoefficient(y, 0);
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System.out.println("Number of constraints = " + solver.numConstraints());
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// [END constraints]
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// [START objective]
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// Maximize x + 10 * y.
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MPObjective objective = solver.objective();
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objective.setCoefficient(x, 1);
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objective.setCoefficient(y, 10);
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objective.setMaximization();
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// [END objective]
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// [START solve]
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final MPSolver.ResultStatus resultStatus = solver.solve();
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// [END solve]
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// [START print_solution]
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if (resultStatus == MPSolver.ResultStatus.OPTIMAL) {
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System.out.println("Solution:");
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System.out.println("Objective value = " + objective.value());
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System.out.println("x = " + x.solutionValue());
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System.out.println("y = " + y.solutionValue());
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} else {
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System.err.println("The problem does not have an optimal solution!");
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}
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// [END print_solution]
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// [START advanced]
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System.out.println("\nAdvanced usage:");
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System.out.println("Problem solved in " + solver.wallTime() + " milliseconds");
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System.out.println("Problem solved in " + solver.iterations() + " iterations");
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System.out.println("Problem solved in " + solver.nodes() + " branch-and-bound nodes");
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// [END advanced]
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}
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private SimpleMipProgram() {}
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}
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// [END program]
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