four balls

Quick and very easy

Spoiler

if you ignore the balls and drop B onto the win. All four levels can be completed in the same manner.

你发四个相同的图，意义何在

@Hyfsy 每一个新的水平，我们减少球的数量

@GFJ and if I remove the robot, will you also cope? quick and easy? ;-)

@Pa$ha Removing B would make it extremely difficult to hit the win. I would have given up fairly soon because the cube is too difficult to control.