/*
* Copyright 2012 JBoss Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.optaplanner.examples.nqueens.solver.score;
import java.util.List;
import org.optaplanner.core.api.score.buildin.simple.SimpleScore;
import org.optaplanner.core.impl.score.director.easy.EasyScoreCalculator;
import org.optaplanner.examples.nqueens.domain.NQueens;
import org.optaplanner.examples.nqueens.domain.Queen;
public class NQueensEasyScoreCalculator implements EasyScoreCalculator<NQueens> {
public SimpleScore calculateScore(NQueens nQueens) {
int n = nQueens.getN();
List<Queen> queenList = nQueens.getQueenList();
int score = 0;
for (int i = 0; i < n; i++) {
for (int j = i + 1; j < n; j++) {
Queen leftQueen = queenList.get(i);
Queen rightQueen = queenList.get(j);
if (leftQueen.getRow() != null && rightQueen.getRow() != null) {
if (leftQueen.getRowIndex() == rightQueen.getRowIndex()) {
score--;
}
if (leftQueen.getAscendingDiagonalIndex() == rightQueen.getAscendingDiagonalIndex()) {
score--;
}
if (leftQueen.getDescendingDiagonalIndex() == rightQueen.getDescendingDiagonalIndex()) {
score--;
}
}
}
}
return SimpleScore.valueOf(score);
}
}