The first meaning: tell the compiler that this name has been matched to a piece of memory (I am married, where will I go?

From where? How to solve the problem, only porridge), the following code uses variables or objects defined elsewhere.

Now a lot of times.

The second meaning: tell the compiler that I kept the name first and can't use it as a variable elsewhere.

Name or object name. For example, if you put a book on a seat in the library study room, it means that this seat has been reserved.

Books, others are not allowed to use this seat any more. In fact, you are not sitting in this seat at this time. This noise

The most typical example of Ming is the declaration of function parameters, such as:

void fun(int i，char c)； Well, we can clearly judge such an explanation: a) it is a definition; B) This is a statement.