第18回オフラインリアルタイムどう書くの解答（Java）

NotFork.java

import static org.junit.Assert.assertEquals;

import java.util.ArrayList;
import java.util.List;

import org.junit.Test;

class Register {

	int power;
	int line = 0;
	int block = -1;

	Register(int p) {
		power = p;
	}

	public void account() {
		if (0 < block) {
			if (power < block) {
				line = line - power;
				block = block - power;
			} else {
				line = line - block + 1;
				block = 1;
			}
		} else {
			if (0 <= line - power) {
				line = line - power;
			} else {
				line = 0;
			}
		}
	}

	public void block() {
		if (block < 0) {
			block = line;
		}
	}
}

/**
 * Q. http://nabetani.sakura.ne.jp/hena/ord18notfork/
 */
public class NotFork {

	List<Register> createRegisters() {
		List<Register> result = new ArrayList<>();
		final int[] throughput = { 2, 7, 3, 5, 2 };
		for (int i : throughput) {
			result.add(new Register(i));
		}
		return result;
	}

	public String solve(String input) {
		List<Register> registers = createRegisters();

		for (int i = 0; i < input.length(); i++) {
			char c = input.charAt(i);
			if (Character.isDigit(c)) {
				line(registers, Integer.valueOf(String.valueOf(c)));
			} else if (c == 'x') {
				int index = line(registers, 1);
				registers.get(index).block();
			} else {
				account(registers);
			}
		}
		return format(registers);
	}

	String format(List<Register> registers) {
		StringBuilder sb = new StringBuilder();
		for (Register regi : registers) {
			sb.append(regi.line);
			sb.append(",");
		}
		String result = sb.toString();
		return result.substring(0, result.length() - 1);
	}

	void account(List<Register> registers) {
		for (Register regi : registers) {
			regi.account();
		}
	}

	int line(List<Register> registers, int n) {
		int result = 0;
		Register target = registers.get(0);
		for (int i = 1; i < registers.size(); i++) {
			if (registers.get(i).line < target.line) {
				target = registers.get(i);
				result = i;
			}
		}
		target.line = target.line + n;
		return result;
	}

	int counter = 0;

	void test(String input, String expected) {
		NotFork target = new NotFork();
		String result = target.solve(input);
		// System.out.println(counter++
		// + (expected.equals(result) ? " OK" : " ****NG****" + result));
		assertEquals(expected, result);
	}

	@Test
	public void testNotFork() throws Exception {
		/* 0 */test("42873x.3.", "0,4,2,0,0");
		/* 1 */test("1", "1,0,0,0,0");
		/* 2 */test(".", "0,0,0,0,0");
		/* 3 */test("x", "1,0,0,0,0");
		/* 4 */test("31.", "1,0,0,0,0");
		/* 5 */test("3x.", "1,1,0,0,0");
		/* 6 */test("99569x", "9,9,6,6,9");
		/* 7 */test("99569x33", "9,9,9,9,9");
		/* 8 */test("99569x33.", "7,2,6,4,7");
		/* 9 */test("99569x33..", "5,0,4,0,5");
		/* 10 */test("12345x3333.", "4,0,3,2,3");
		/* 11 */test("54321x3333.", "3,0,3,0,4");
		/* 12 */test("51423x3333.", "3,4,4,0,4");
		/* 13 */test("12x34x.", "1,0,1,0,2");
		/* 14 */test("987x654x.32", "7,6,4,10,5");
		/* 15 */test("99999999999x99999999.......9.", "20,10,12,5,20");
		/* 16 */test("997", "9,9,7,0,0");
		/* 17 */test(".3.9", "1,9,0,0,0");
		/* 18 */test("832.6", "6,6,0,0,0");
		/* 19 */test(".5.568", "3,5,6,8,0");
		/* 20 */test("475..48", "4,8,0,0,0");
		/* 21 */test("7.2..469", "1,4,6,9,0");
		/* 22 */test("574x315.3", "3,3,1,7,1");
		/* 23 */test("5.2893.x98", "10,9,5,4,1");
		/* 24 */test("279.6xxx..4", "2,1,4,1,1");
		/* 25 */test("1.1.39..93.x", "7,1,0,0,0");
		/* 26 */test("7677749325927", "16,12,17,18,12");
		/* 27 */test("x6235.87.56.9.", "7,2,0,0,0");
		/* 28 */test("4.1168.6.197.6.", "0,0,3,0,0");
		/* 29 */test("2.8.547.25..19.6", "6,2,0,0,0");
		/* 30 */test(".5.3x82x32.1829..", "5,0,5,0,7");
		/* 31 */test("x.1816..36.24.429.", "1,0,0,0,7");
		/* 32 */test("79.2.6.81x..26x31.1", "1,0,2,1,1");
		/* 33 */test("574296x6538984..5974", "14,13,10,15,14");
		/* 34 */test("99.6244.4376636..72.6", "5,6,0,0,3");
		/* 35 */test("1659.486x5637168278123", "17,16,16,18,17");
		/* 36 */test(".5.17797.x626x5x9457.3.", "14,0,3,5,8");
		/* 37 */test("..58624.85623..4.7..23.x", "1,1,0,0,0");
		/* 38 */test("716.463.9.x.8..4.15.738x4", "7,3,5,8,1");
		/* 39 */test("22xx.191.96469472.7232377.", "10,11,18,12,9");
		/* 40 */test("24..4...343......4.41.6...2", "2,0,0,0,0");
		/* 41 */test("32732.474x153.866..4x29.2573", "7,5,7,8,5");
		/* 42 */test("786.1267x9937.17.15448.1x33.4", "4,4,8,4,10");
		/* 43 */test("671714849.149.686852.178.895x3", "13,16,13,10,12");
		/* 44 */test("86x.47.517..29621.61x937..xx935", "7,11,8,8,10");
		/* 45 */test(".2233.78x.94.x59511.5.86x3.x714.", "4,6,10,8,8");
		/* 46 */test(".793...218.687x415x13.1...x58576x", "8,11,8,6,9");
		/* 47 */test("6.6x37.3x51x932.72x4x33.9363.x7761", "15,13,15,12,15");
		/* 48 */test("6..4.x187..681.2x.2.713276.669x.252", "6,7,8,6,5");
		/* 49 */test(".6.xx64..5146x897231.x.21265392x9775", "19,17,19,20,17");
		/* 50 */test("334.85413.263314.x.6293921x3.6357647x", "14,14,12,16,10");
		/* 51 */test("4.1..9..513.266..5999769852.2.38x79.x7", "12,10,13,6,10");
	}
}