230511 거리두기 확인하기

int[] dx = { 0, 1, 0, -1 };
int[] dy = { -1, 0, 1, 0 };

public int[] solution(String[][] places) {
    int[] result = new int[places.length];
    for (int i = 0; i < places.length; i++) {
        result[i] = isCorrext(places[i]);
    }
    return result;
}

public int isCorrext(String[] board) {
    for (int i = 0; i < board.length; i++) {
        for (int j = 0; j < board[i].length(); j++) {
            if (board[i].charAt(j) == 'P') {
                if (!bfs(board, i, j))
                    return 0;
            }
        }
    }
    return 1;
}

static boolean bfs(String[] p, int x, int y) {
    Queue<int[]> queue = new LinkedList<>();
    queue.add(new int[] { x, y });

    int[] dx = { 1, -1, 0, 0 };
    int[] dy = { 0, 0, 1, -1 };

    while (!queue.isEmpty()) {
        int[] temp = queue.poll();
        for (int i = 0; i < 4; i++) {
            int nx = temp[0] + dx[i];
            int ny = temp[1] + dy[i];

            if ((nx < 0 || ny < 0 || nx >= 5 || ny >= 5) || (nx == x && ny == y)) {
                continue;
            }

            int m = Math.abs(x - nx) + Math.abs(y - ny);

            if (p[nx].charAt(ny) == 'P' && m <= 2) {
                return false;
            } else if (p[nx].charAt(ny) == 'O' && m < 2) {
                queue.add(new int[] { nx, ny });
            }
        }
    }
    return true;
}

출처:https://school.programmers.co.kr/learn/courses/30/lessons/81302