typedef means type definition, that is, type define

typedef ?int ?TElemType represents: alias of int: For example, you usually define an integer data type like this: int a;< /p>

After the type definition (typedef int TElementType), you can define it like this: TElementType a;

typedef int add(int a);

The int ()(int) function declaration type of add is defined.

add ?myadd; ?This declares the ?int myadd(int); function.

add * pmyadd; This defines int (*pmyadd)(int); function pointer.