48 lines
1.6 KiB
Java
48 lines
1.6 KiB
Java
// Copyright 2010-2018 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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import com.google.ortools.sat.CpModel;
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import com.google.ortools.sat.CpSolver;
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import com.google.ortools.sat.CpSolverStatus;
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import com.google.ortools.sat.IntVar;
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/**
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* In a field of rabbits and pheasants, there are 20 heads and 56 legs. How many rabbits and
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* pheasants are there?
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*/
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public class RabbitsAndPheasantsSat {
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static {
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System.loadLibrary("jniortools");
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}
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public static void main(String[] args) throws Exception {
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// Creates the model.
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CpModel model = new CpModel();
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// Creates the variables.
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IntVar r = model.newIntVar(0, 100, "r");
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IntVar p = model.newIntVar(0, 100, "p");
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// 20 heads.
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model.addSumEqual(new IntVar[] {r, p}, 20);
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// 56 legs.
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model.addLinearExpressionEqual(new IntVar[] {r, p}, new long[] {4, 2}, 56);
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// Creates a solver and solves the model.
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CpSolver solver = new CpSolver();
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CpSolverStatus status = solver.solve(model);
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if (status == CpSolverStatus.FEASIBLE) {
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System.out.println(solver.value(r) + " rabbits, and " + solver.value(p) + " pheasants");
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}
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}
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}
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