64 lines
2.2 KiB
Java
64 lines
2.2 KiB
Java
// Copyright 2010-2012 Google
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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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package com.google.ortools.constraintsolver.samples;
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import com.google.ortools.constraintsolver.DecisionBuilder;
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import com.google.ortools.constraintsolver.IntVar;
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import com.google.ortools.constraintsolver.Solver;
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import java.util.logging.Logger;
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/**
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* Sample showing how to model using the constraint programming solver.
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*
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*/
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public class RabbitsPheasants {
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private static Logger logger =
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Logger.getLogger(RabbitsPheasants.class.getName());
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static {
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System.loadLibrary("jniconstraintsolver");
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}
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/**
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* Solves the rabbits + pheasants problem. We are seing 20 heads
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* and 56 legs. How many rabbits and how many pheasants are we thus
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* seeing?
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*/
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private static void solve() {
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Solver solver = new Solver("RabbitsPheasants");
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IntVar rabbits = solver.makeIntVar(0, 100, "rabbits");
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IntVar pheasants = solver.makeIntVar(0, 100, "pheasants");
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solver.addConstraint(solver.makeEquality(solver.makeSum(rabbits, pheasants),
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20));
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solver.addConstraint(solver.makeEquality(solver.makeSum(
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solver.makeProd(rabbits, 4),
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solver.makeProd(pheasants, 2)), 56));
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DecisionBuilder db = solver.makePhase(rabbits, pheasants,
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solver.CHOOSE_FIRST_UNBOUND,
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solver.ASSIGN_MIN_VALUE);
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solver.newSearch(db);
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solver.nextSolution();
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logger.info(rabbits.toString());
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logger.info(pheasants.toString());
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solver.endSearch();
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}
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public static void main(String[] args) throws Exception {
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RabbitsPheasants.solve();
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}
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}
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