第3回 オフラインリアルタイムどう書くの参考問題（Enum編）

BallCountEx.java

import static org.junit.Assert.assertEquals;
import org.junit.Test;

enum Rule {
  s {
		@Override
		int[] play(int[] count) {
			count[1] += 1;
			if (count[1] == 3) {
				count[0] += 1;
				count[1] = 0;
			}
			return count;
		}
	},
	b {
		@Override
		int[] play(int[] count) {
			if ((count[2] += 1) == 4) {
				count[1] = 0;
				count[2] = 0;
			}
			return count;
		}
	},
	f {
		@Override
		int[] play(int[] count) {
			if (count[1] < 2) {
				count[1] += 1;
			}
			return count;
		}
	},
	h {
		@Override
		int[] play(int[] count) {
			count[1] = 0;
			count[2] = 0;
			return count;
		}
	},
	p {
		@Override
		int[] play(int[] count) {
			count[0] += 1;
			count[1] = 0;
			count[2] = 0;
			return count;
		}
	};
	abstract int[] play(int[] count);
}

/**
 * 問題: http://qiita.com/items/ebd8a56b41711ba459f9
 */
public class BallCountEx {
	public String solve(String input) {
		int[] count = new int[3]; // out, strike, ball
		char[] charArray = input.toCharArray();

		String result = "";
		for (char each : charArray) {
			Rule rule = Rule.valueOf(String.valueOf(each));
			count = rule.play(count);
			count = outCheck(count);
			for (int i : count) {
				result += i;
			}
			result += ",";
		}
		return result.substring(0, result.length() - 1);
	}

	private int[] outCheck(int[] count) {
		if (count[0] == 3) {
			count[0] = 0;
			count[1] = 0;
			count[2] = 0;
		}
		return count;
	}

	@Test
	public void testName() throws Exception {
		BallCountEx bc = new BallCountEx();
		assertEquals("010", bc.solve("s"));
		assertEquals("010,020,100", bc.solve("sss"));
		assertEquals("001,002,003,000", bc.solve("bbbb"));
		assertEquals("010,020,021,022,023,000", bc.solve("ssbbbb"));
		assertEquals("000,010,011,000,010,000,001,000", bc.solve("hsbhfhbh"));
		assertEquals("100,110,111,200,210,000,001,100", bc.solve("psbpfpbp"));
		assertEquals("100,200,000", bc.solve("ppp"));
		assertEquals("010,020,020,020,100", bc.solve("ffffs"));
		assertEquals("010,020,100,200,210,220,220,000", bc.solve("ssspfffs"));
		assertEquals("001,002,003,013,023,000,100,200,000",
				bc.solve("bbbsfbppp"));
		assertEquals(
				"010,020,100,101,102,103,100,110,111,100,110,111,200,000,100",
				bc.solve("sssbbbbsbhsbppp"));
		assertEquals("010,020,020,020,100,110,120,200,210,000",
				bc.solve("ssffpffssp"));
	}
}