状态机演示程序。开始时，开始按钮点亮，点击下一步，表示状态的布尔灯顺序点亮，点击下一步，按照状态三、二、一变化。-State machine demonstration program. Initially, the Start button is lit, click Next, indicate the state of the Boolean lights illuminate sequentially, click Next and follow the state three, two