第6回オフラインリアルタイムどう書くの問題 Javaで回答

挑戦!

package how;

public class JudgeZokugara {

    /** 続柄：本人 */
    private static final String HONNIN =  "me";
    /** 続柄：母 */
    private static final String HAHA =  "mo";
    /** 続柄：娘 */
    private static final String MUSUME =  "da";
    /** 続柄：姉妹 */
    private static final String SIMAI =  "si";
    /** 続柄：おば */
    private static final String OBA =  "au";
    /** 続柄：姪 */
    private static final String MEI =  "ni";
    /** 続柄：いとこ */
    private static final String ITOKO =  "co";
    /** 続柄：その他 */
    private static final String OTHER =  "-";

    /**
     * 判定メソッド
     * @param relation 関係
     * @return 続柄
     */
    private static String judge(String relation) {

        // relation(a->b)を"a"と"b"に分解
        int from = Integer.valueOf(relation.split("->")[0]);
        int to = Integer.valueOf(relation.split("->")[1]);
        // fromとtoが同値であれば本人
        if (from == to) {
            return HONNIN;
        }

        // 世代判定
        // fromの世代判定
        int fromGene = isGeneration(from);
        // toの世代判定
        int toGene = isGeneration(to);
        if (fromGene == toGene) {
            // 世代が同じ
            if(getParentNo(from) == getParentNo(to)) {
                // 親が同じ => 姉妹
                return SIMAI;
            } else {
                // 親が違う
                if (getParentNo(getParentNo(from)) == getParentNo(getParentNo((to)))) {
                    // 祖母が同じ => 従姉妹
                    return ITOKO;
                } else {
                    return OTHER;
                }
            }
        } else if (fromGene > toGene) {
            // toがfromより世代が1つ上 => 母 or おば
            // それ以外 => その他の続柄
            if (fromGene-1 == toGene) {
                if (to == getParentNo(from)) {
                    // fromの親番号がtoと同じ => 母
                    return HAHA;
                } else {
                    if (getParentNo(to) == getParentNo(getParentNo(from))) {
                        // fromの祖母がtoの母と同じ => おば
                        return OBA;
                    }
                }
                // fromの祖母がtoの母と違う => その他
                return OTHER;
            }
            return OTHER;
        } else {
            // fromがtoより世代が1つ上 => 娘 or 姪
            // それ以外 => その他の続柄
            if (fromGene+1 == toGene) {
                if (from == getParentNo(to)) {
                    // toの親番号がfromと同じ => 娘
                    return MUSUME;
                } else {
                    if (getParentNo(from) == getParentNo(getParentNo(to))) {
                        // toの祖母がfromの母と同じ => 姪
                        return MEI;
                    }
                }
                // toの祖母がfromの母と違う => その他
                return OTHER;
            }
            return OTHER;
        }
    }

    /**
     * 世代判定
     * @param num
     * @return 世代番号（第1世代：0,第2世代:1）
     */
    private static int isGeneration(int num) {
        int gene = 0;
        int start = 1;
        int end = 1;
        if (1 < num) {
            gene = 1;
            while (gene<=3) {
                start = start + (int)Math.pow(3,gene-1);
                end = end + (int)Math.pow(3,gene);
                if (start <= num
                        && end >= num) {
                    break;
                }
                gene++;
            }
        }
        return gene;
    }

    /**
     * 親の番号を返却する。
     * @param no
     * @return
     */
    private static int getParentNo(int no) {
        int parentNo = 1;

        if (0==no%3) {
            parentNo = no/3;
        } else if ((no-1)%3==0) {
            parentNo = (no-1)/3;
        } else if ((no+1)%3==0) {
            parentNo = (no+1)/3;
        }


        return parentNo;
    }

    /**
     * テスト実行メソッド
     * @param relation 関係
     * @param exp 結果の期待値
     */
    private static void test(String relation, String exp) {
        // 判定
        if (exp.equals(judge(relation))) {
            System.out.println(relation + " : " + exp + " => OK" );
        } else {
            System.out.println(relation + " : " + exp + " => NG" );
        }
    }

    /**
     * 実行メソッド
     * @param args
     */
    public static void main(String[] args) {
        /*#0*/ test( "5->2", "mo" );
        /*#1*/ test( "28->10", "au" );
        /*#2*/ test( "1->1", "me" );
        /*#3*/ test( "40->40", "me" );
        /*#4*/ test( "27->27", "me" );
        /*#5*/ test( "7->2", "mo" );
        /*#6*/ test( "40->13", "mo" );
        /*#7*/ test( "9->3", "mo" );
        /*#8*/ test( "4->1", "mo" );
        /*#9*/ test( "1->3", "da" );
        /*#10*/ test( "12->35", "da" );
        /*#11*/ test( "3->8", "da" );
        /*#12*/ test( "6->19", "da" );
        /*#13*/ test( "38->40", "si" );
        /*#14*/ test( "9->8", "si" );
        /*#15*/ test( "4->2", "si" );
        /*#16*/ test( "15->16", "si" );
        /*#17*/ test( "40->12", "au" );
        /*#18*/ test( "10->4", "au" );
        /*#19*/ test( "21->5", "au" );
        /*#20*/ test( "8->2", "au" );
        /*#21*/ test( "3->5", "ni" );
        /*#22*/ test( "11->39", "ni" );
        /*#23*/ test( "2->13", "ni" );
        /*#24*/ test( "13->32", "ni" );
        /*#25*/ test( "14->22", "co" );
        /*#26*/ test( "40->34", "co" );
        /*#27*/ test( "5->8", "co" );
        /*#28*/ test( "12->10", "co" );
        /*#29*/ test( "1->27", "-" );
        /*#30*/ test( "8->1", "-" );
        /*#31*/ test( "12->22", "-" );
        /*#32*/ test( "2->40", "-" );
        /*#33*/ test( "32->31", "-" );
        /*#34*/ test( "13->14", "-" );
    }
}

多分、無駄がいっぱいある・・・