230426 미로 탈출

static class Position {
    int x;
    int y;
    int level;

    public Position(int x, int y, int level) {
        this.x = x;
        this.y = y;
        this.level = level;
    }
}

static char[][] map;
static boolean[][] visited;
static int[] dx = { -1, 0, 1, 0 };
static int[] dy = { 0, 1, 0, -1 };

public static int solution(String[] maps) {
    int answer = 0;
    int row = maps.length;
    int col = maps[0].length();

    map = new char[row][col];
    visited = new boolean[row][col];

    Position startPosition = null;
    Position leverPosition = null;
    Position endPosition = null;

    for (int i = 0; i < row; i++) {
        for (int j = 0; j < col; j++) {
            char c = maps[i].charAt(j);

            if (c == 'S') {
                startPosition = new Position(i, j, 0);
            }
            if (c == 'L') {
                leverPosition = new Position(i, j, 0);
            }
            if (c == 'E') {
                endPosition = new Position(i, j, 0);
            }

            map[i][j] = c;
        }
    }

    answer = bfs(startPosition.x, startPosition.y, leverPosition.x, leverPosition.y, maps.length, maps[0].length());

    return answer == -1 ? -1 : toEnd(maps, answer, leverPosition, endPosition);
}

private static int toEnd(String[] maps, int answer, Position leverPosition, Position endPosition) {
    visited = new boolean[map.length][map[0].length];
    int temp = bfs(leverPosition.x, leverPosition.y, endPosition.x, endPosition.y, maps.length, maps[0].length());

    if (temp == -1) {
        answer = -1;
    } else {
        answer += temp;
    }
    return answer;
}

public static int bfs(int startX, int startY, int endX, int endY, int height, int width) {
    Queue<Position> q = new LinkedList<>();
    q.add(new Position(startX, startY, 0));
    visited[startX][startY] = true;

    while (!q.isEmpty()) {
        Position now = q.poll();
        int x = now.x;
        int y = now.y;
        int level = now.level;

        if (x == endX && y == endY) {
            return level;
        }

        for (int i = 0; i < 4; i++) {
            int nowX = x + dx[i];
            int nowY = y + dy[i];

            if (nowX < 0 || nowX >= height || nowY < 0 || nowY >= width) {
                continue;
            }

            if (!visited[nowX][nowY] && map[nowX][nowY] != 'X') {
                q.add(new Position(nowX, nowY, level + 1));
                visited[nowX][nowY] = true;
            }
        }
    }

    return -1;
}

출처:https://school.programmers.co.kr/learn/courses/30/lessons/159993