Well, this block here on the left that I came counter counter=0 up with arbitrarily sets a variable called counter equal to 0 and then it forever says that counters value 1 and then it changes the counter by 1.

大家看一下左边的这一段代码,其中有一个随便定义的变量,它会一直显示counter的值,每显示一次，counter加。

哈佛公开课 - 计算机科学课程节选