I'm reminded of the confirmation screen here and that's not too bad, then we put in the card and we click confirm and then finally we see the swap Then finally literally nine steps later the ticket comes out of the machine and then, frankly, had to go through the process of where to put the ticket in the machines.

这里出现了确认画面,那还不是太坏，然后我们把卡插进去,点击确认，然后我们看到了那个,函数。，swap，function。,【笑声】然后最终经过9个步骤,票从机器中出来了，然后，需要找出从哪里,把票放到机器中去。

哈佛公开课 - 计算机科学课程节选