- Well -- and I'll fix this blue next time -- I'm first telling the compiler I need access to the standard io library because printf is declared there.

哦！--下次我把这个字体颜色改成蓝色的-,我先告诉编译器--我需要使用,标准输入输出库,因为printf在那个库里面申明的。

哈佛公开课 - 计算机科学课程节选

stdio c So somewhere there's standard IO dot C, stdio h somewhere they're standard IO dot H, but, for me, right now, the only file I need to know about is the dot H, -- because what Sharp include really does -- it's what's called a preprocessor directive.

所以某个地方有一个，现在对于我来说它们是，我只要知道那个，h文件，因为Sharp包含的-,叫做预处理指令。

哈佛公开课 - 计算机科学课程节选