You could run through a little loop to say keep trying until you get one. But one of the ways I could deal with it is what's shown here.

你可以运行一个小循环来不断地做,直到得到一个输入,但你应该做的是弄明白这里到底要干什么。

麻省理工公开课 - 计算机科学及编程导论课程节选

Ah ha, it goes into that accept portion, prints out a message, and goes back around the while loop to say try again. And it's going to keep doing this until I give it something that does serve as a float.

他会说输入一个浮点数，啊哈，它就到了那段处理代码,打印出消息,然后回到while循环让我们再输一次,它会持续这么做直到它接受到一个浮点数。

麻省理工公开课 - 计算机科学及编程导论课程节选