Sams Teach Yourself C in 21 Days

Pointers: Beyond the Basics 435

15

Q Is there a difference between a pointer to a string and a pointer to an array of

characters?

ANo. A string can be considered an array of characters.

Q Is it necessary to use the concepts presented in today’s lesson to take advan-

tage of C?

AYou can use C without ever using any advanced pointer concepts; however, you

won’t take advantage of the power that C offers. Pointer manipulations such as

those shown in today’s lesson can make many programming tasks easier and more

efficient.

Q Are there other times when function pointers are useful?

AYes. Pointers to functions also are used with menus. Based on a value returned

from a menu, a pointer is set to the function that should be called based on the

menu choice.

Q Name two major advantages of linked lists.

AOne: The size of a linked list can be increased or decreased while the program is

running; it doesn’t have to be predefined when you write the code. Two: It’s easy

to keep a linked list in sorted order, because elements can easily be added or

deleted anywhere in the list.

Workshop ............................................................................................................

The Workshop provides quiz questions to help you solidify your understanding of the

material covered and exercises to provide you with experience in using what you’ve

learned.

Quiz ..............................................................................................................

1. Write code that declares a type floatvariable, declares and initializes a pointer to
   the variable, and declares and initializes a pointer to the pointer.


2. Continuing with the example in question 1, say that you want to use the pointer to
   a pointer to assign the value 100 to the variable x. What, if anything, is wrong with
   the following assignment statement?
   *ppx = 100;
   If it isn’t correct, how should it be written?


3. Assume that you have declared an array as follows:
   int array[2][3][4];
   What is the structure of this array, as seen by the C compiler?

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