第1回オフラインリアルタイムどう書くJavaでの解答

Tick-Tack-Toeの解答
実行方法: java tictactoe/Main < input.txt

Main.java

package tictactoe;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {
	//反則だったり、どちらかが勝ったらtrueを返す。
	private static String finished(int[] stage, int i, int pos) {
		if(!isRegal(stage, pos)) {
			return String.format("Foul : %s won.", (i % 2 == 1)?"o": "x");
		} else {
			stage[pos] = (i % 2 == 0)? 1 : 2;
			if(isFill(stage, pos)) {
				return String.format("%s won.", (i % 2 == 0)? "o" : "x");
			}
		}
		return null;
	}
	private static boolean isFill(int[] stage, int pos) {
		int v = stage[pos];
		int x = pos % 3;
		int y = pos / 3;
		boolean a = (stage[position((x + 1) % 3, y)] == v && stage[position((x + 2) % 3, y)] == v) ||
		            (stage[position(x, (y + 1) % 3)] == v && stage[position(x, (y + 2) % 3)] == v);
		boolean b = (stage[0] == stage[4] && stage[4] == stage[8] && stage[4] != 0) ||
				    (stage[2] == stage[4] && stage[4] == stage[6] && stage[4] != 0);
		return a || b;
	}
	private static int position(int x, int y) {
		return x + y * 3;
	}
	private static boolean isRegal(int[] stage, int pos) {
		return stage[pos] == 0;
	}
	private static String game(String inp) {
		// ○: 1, ×: 2
		int[] stage = new int[9];
		char[] chs = inp.toCharArray();
		String msg = null;
		for(int i = 0; i < 9; i++) {
			if((msg = finished(stage, i, (int)(chs[i] - '0')-1)) != null) return msg;
		}
		return "Draw game.";
	}
	public static void main(String[] args) {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		try {
			String line = null;
			while ((line = br.readLine()) != null) {
				String[] a = line.split("\\t");
				if(game(a[1]).equals(a[2])) {
					System.out.println(a[0] + ":" + game(a[1]));
				} else {
					System.out.println(a[0] + ":" + a[1]);
					System.out.println("actual  :\"" + game(a[1]) +"\"");
					System.out.println("expected:\"" + a[2] +"\"");
				}
			}
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

input.txt

1	79538246	x won.
2	35497162193	x won.
3	61978543	x won.
4	254961323121	x won.
5	6134278187	x won.
6	4319581	Foul : x won.
7	9625663381	Foul : x won.
8	7975662	Foul : x won.
9	2368799597	Foul : x won.
10	18652368566	Foul : x won.
11	965715	o won.
12	38745796	o won.
13	371929	o won.
14	758698769	o won.
15	42683953	o won.
16	618843927	Foul : o won.
17	36535224	Foul : o won.
18	882973	Foul : o won.
19	653675681	Foul : o won.
20	9729934662	Foul : o won.
21	972651483927	Draw game.
22	5439126787	Draw game.
23	142583697	Draw game.
24	42198637563	Draw game.
25	657391482	Draw game.