您的一或更多的导函数似乎是不确定的。

One or more of your derivatives appears to be undefined.

youdao

不管在哪里声明一个变量或函数，extern关键字都允许其他文件在不确定其定义位置的情况下使用该文件。

No matter where you declare a variable or function, the extern keyword allows other files to use it without knowing where it was defined.

youdao

该函数接受两个参数，第一个是随机生成的1到1,000,000之间的数字——但我们不确定具体是不是在此范围内。

It takes two parameters and the first is a randomly generated number between 1 and 1 million - but are they?

youdao