案例分析题根据数据模型的应用目的不同,数据模型可分为();而根据数据结构的类型,数据模型又可分为()。 根据数据模型的应用目的不同,数据模型可分为()
A. 概念模型和层次模型
B. 概念模型和数据模型
C. 层次模型,分布模型和网状膜型
D. 层次模型,网状模型和关系模型
案例分析题As mentioned above, C imposes relatively few built - in ways of doing things on the program- mer. Some common tasks, such as manipulating (66) , (67) , and doing (68) (I/O), are performed by calling on library functions. Other tasks which you might want to do, such as creating or listing directories, or interacting with a mouse, or displaying windows or other (69) elements, or doing color graphics, are not defined by the C language at all. You can do these things from a C program, of course, but you will be calling on services which are peculiar to your programming environment (70) , processor, and operating system) and which are not defined by the C standard. Since this course is about portable C programming, it will also be steering clear of facilities not provided in all C environments. (68)处应选择()
A. input/output
B. inoptimization/optimization
C. inside/outside
D. inordinacy/ordinance