第五回オフライリアルタイムどう書く の部分問題のJava解答

DahimiPart.java

import static org.junit.Assert.assertEquals;

import static org.junit.Assert.assertEquals;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;

import org.junit.Test;

class Card implements Comparable<Card> {
	String suit;
	String rank;

	Card(char s, char r) {
		suit = String.valueOf(s);
		rank = String.valueOf(r);
	}

	public boolean isStrong(int rank) {
		int n = this.convertRank();
		if (rank < n) {
			return true;
		}
		return false;
	}

	@Override
	public String toString() {
		return suit + rank;
	}

	public int convertRank() {
		if (rank.equals("T")) {
			return 10;
		}
		if (rank.equals("J")) {
			return 11;
		}
		if (rank.equals("Q")) {
			return 12;
		}
		if (rank.equals("K")) {
			return 13;
		}
		if (rank.equals("A")) {
			return 14;
		}
		if (rank.equals("2")) {
			return 15;
		}
		if (rank.equals("o")) {
			return 16;
		}
		return Integer.valueOf(rank);
	}

	@Override
	public int compareTo(Card o) {
		int n = this.convertRank();
		int m = o.convertRank();
		if (m < n) {
			return 1;
		}
		if (n < m) {
			return -1;
		}
		return 0;
	}

	@Override
	public boolean equals(Object obj) {
		if (obj instanceof Card) {
			Card c = (Card) obj;
			if (rank.equals(c.rank) && suit.equals(c.suit)) {
				return true;
			}
		}
		return false;
	}
}

/**
 * 問題（部分問題の解答）: http://nabetani.sakura.ne.jp/hena/ord5dahimi/
 */
public class DahimiPart {

	protected String solve(String input) {
		String[] split = input.split(",");
		if (split.length < 2) {
			return "-";
		}
		List<Card> spaceList = getCards(split[0]);
		List<Card> hand = getCards(split[1]);
		int spaceRank = getMinRank(spaceList).convertRank();

		return getResult(spaceRank, hand);
	}

	protected String getResult(int spaceRank, List<Card> hand) {
		List<Card> cards = new ArrayList<>();
		for (Card card : hand) {
			if (card.isStrong(spaceRank)) {
				cards.add(card);
			}
		}
		if (cards.size() == 0) {
			return "-";
		}

		String result = cards.get(0).toString();
		for (int i = 1; i < cards.size(); i++) {
			result += "," + cards.get(i).toString();
		}
		return result;
	}

	protected Card getMinRank(List<Card> space) {
		if (hasJoker(space)) {
			if (space.size() == 1) {
				return new Card('J', 'o');
			}
			space.remove(new Card('J', 'o'));
		}
		return Collections.min(space);
	}

	protected boolean hasJoker(List<Card> hand) {
		return 0 < Collections.frequency(hand, new Card('J', 'o')) ? true
				: false;
	}

	protected List<Card> getCards(String hand) {
		List<Card> result = new ArrayList<>();
		for (int i = 0; i < hand.length(); i += 2) {
			Card c = new Card(hand.charAt(i), hand.charAt(i + 1));
			result.add(c);
		}
		return result;
	}

	public static void main(String[] args) {
		DahimiPart dahimi = new DahimiPart();
		System.out.println(dahimi.solve("JoC8,H6D7C5S9CQH9STDTCAD9S5DAS2CT"));
	}

	// 解答や期待値の文字列をソートする
	protected String answerSort(String string) {
		String result = "";
		String[] split = string.split(",");
		if (split.length == 0) {
			// カンマがない場合は'-'、あるいは1枚だけ
			return string;
		}

		List<String> tmpOuter = new ArrayList<>();
		int innerUnit = split[0].length() / 2;
		for (String str : split) {
			List<String> tmpInner = new ArrayList<>();
			for (int i = 0; i < innerUnit * 2; i += 2) {
				String s = new Card(str.charAt(i), str.charAt(i + 1))
						.toString();
				tmpInner.add(s);
			}
			Collections.sort(tmpInner);
			StringBuilder inner = new StringBuilder();
			for (String s : tmpInner) {
				inner.append(s);
			}
			tmpOuter.add(new String(inner));
		}

		Collections.sort(tmpOuter);
		Iterator<String> ite = tmpOuter.iterator();
		if (ite.hasNext()) {
			result += ite.next() + ",";
		}
		return result.substring(result.length() - 1);
	}

	protected void test(String problem, String expect) {
		String expectSort = answerSort(expect);

		DahimiPart dahimi = new DahimiPart();
		String answer = dahimi.solve(problem);
		String answerStr = answerSort(answer);

		assertEquals(expectSort, answerStr);
	}

	@Test
	public void testSolve() throws Exception {
		/* #1 */test("DJ,", "-");
		/* #2 */test("H7,HK", "HK");
		/* #3 */test("S3,D4D2", "D4,D2");
		/* #4 */test("S9,C8H4", "-");
		/* #5 */test("S6,S7STCK", "CK,ST,S7");
		/* #6 */test("H4,SAS8CKH6S4", "S8,CK,H6,SA");
		/* #7 */test("ST,D6S8JoC7HQHAC2CK", "Jo,C2,CK,HA,HQ");
		/* #8 */test("SA,HAD6S8S6D3C4H2C5D4CKHQS7D5", "H2");
		/* #9 */test("S2,D8C9D6HQS7H4C6DTS5S6C7HAD4SQ", "-");
		/* #10 */test("Jo,HAC8DJSJDTH2", "-");
	}
}