874. Walking Robot Simulation 

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class Solution {

    private static final int[][] DIRECTIONS = new int[][]{{0, 1}, {1, 0}, {0, -1}, {-1, 0}}; // 上，右，下，左

    public int robotSim(int[] commands, int[][] obstacles) {
        int maxDistanceSquare = 0;

        Map<Integer, Set<Integer>> obstacleMap = new HashMap<>();
        for (int[] obstacle : obstacles) {
            obstacleMap.computeIfAbsent(obstacle[0], key -> new HashSet<>()).add(obstacle[1]);
        }

        int i = 0, j = 0;
        int directionIndex = 0; // 初始化方向为上
        for (int command : commands) {
            if (command == -2) {
                // 左转
                directionIndex = (directionIndex - 1 + DIRECTIONS.length) % DIRECTIONS.length;
            } else if (command == -1) {
                // 右转
                directionIndex = (directionIndex + 1) % DIRECTIONS.length;
            } else {
                // 向前移动
                int[] direction = DIRECTIONS[directionIndex];
                for (int k = 0; k < command; k++) {
                    int nextI = i + direction[0];
                    int nextJ = j + direction[1];
                    if (obstacleMap.getOrDefault(nextI, Collections.emptySet()).contains(nextJ)) {
                        break;
                    } else {
                        i = nextI;
                        j = nextJ;
                        maxDistanceSquare = Math.max(maxDistanceSquare, i * i + j * j);
                    }
                }
            }
        }

        return maxDistanceSquare;
    }
    
}

References

874. Walking Robot Simulation