백준 2615번 오목

2615번 오목

문제

난이도

• Silver2

알고리즘 분류

• 구현
• 브루트포스 알고리즘

풀이

public class Main {

    static int[] dx = { -1, 1, 0, 0, -1, 1, -1, 1 }; // |,-, \, /
    static int[] dy = { 0, 0, -1, 1, -1, 1, 1, -1 };
    static int[][] map = new int[19][19];

    static boolean check(int color, int x, int y) {
        return x > 18 || x < 0 || y > 18 || y < 0 || map[x][y] != color;
    }

    static int[] count(int color, int x, int y, int idx) {
        int ansX = x;
        int ansY = y;
        int newX = x;
        int newY = y;
        int cnt = 0;
        for (int j = 0; j < 19; j++) {
            newX += dx[idx];
            newY += dy[idx];
            if (check(color, newX, newY)) {
                break;
            }
            cnt++;
            if (newY < ansY) {
                ansX = newX;
                ansY = newY;
            }
            if (newY == ansY) {
                ansX = Math.min(ansX, newX);
            }
        }
        return new int[] { cnt, ansX, ansY };
    }

    static int[] solution(int color, int x, int y) {

        int[] answer = { 0, 0, 0 };

        for (int i = 0; i < 4; i++) {
            int[] arr1 = count(color, x, y, i * 2);
            int[] arr2 = count(color, x, y, i * 2 + 1);
            int count = arr1[0] + arr2[0] + 1;

            if (count == 5) {
                answer[0] = color;
                int ansX;
                int ansY;

                int x1 = arr1[1];
                int y1 = arr1[2];
                int x2 = arr2[1];
                int y2 = arr2[2];

                if (y1 < y2) {
                    ansY = y1;
                    ansX = x1;
                } else if (y1 > y2) {
                    ansY = y2;
                    ansX = x2;
                } else {
                    ansY = y1;
                    ansX = Math.min(x1, x2);
                }

                answer[1] = ansX + 1;
                answer[2] = ansY + 1;
                return answer;
            }
        }
        return answer;
    }

    public static void main(String[] args) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

        int[] result = new int[3];

        for (int i = 0; i < 19; i++) {
            StringTokenizer st = new StringTokenizer(br.readLine());
            for (int j = 0; j < 19; j++) {
                int n = Integer.parseInt(st.nextToken());
                map[i][j] = n;
            }
        }
        loop: for (int i = 0; i < 19; i++) {
            for (int j = 0; j < 19; j++) {
                if (map[i][j] == 0) {
                    continue;
                }
                if (map[i][j] == 1) {
                    result = solution(1, i, j);
                }
                if (map[i][j] == 2) {
                    result = solution(2, i, j);
                }
                if (result[0] != 0) {
                    bw.write(result[0] + "\n" + result[1] + " " + result[2]);
                    bw.close();
                    break loop;
                }
            }
        }
        if (result[0] == 0) {
            bw.write("0");
            bw.close();
        }
    }
}

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