规则Rules：
标准数独基础上，涂色格等于其左右两侧数字之差，也等于其上下两侧数字之差。
Classic rules applied. Additionally, the colored cell equals to the difference between the numbers on the left and right sides, as well as the difference between the numbers on the top and bottom sides.
*规则经过修改，以此版本👆为准。
The rules have been modified, use rules as this version 👆.
