Sams Teach Yourself C in 21 Days

Pointers: Beyond the Basics 437

15

Exercises ........................................................................................................

1. Write a declaration for a pointer to a function that takes an integer as an argument
   and returns a type floatvariable.


2. Write a declaration for an array of pointers to functions. The functions should all
   take a character string as a parameter and return an integer. What could such an
   array be used for?


3. Write a statement to declare an array of 10 pointers to type char.
   4.BUG BUSTER:Is anything wrong with the following code?
   int x[3][12];
   int *ptr[12];
   ptr = x;


4. Write a structure that is to be used in a single-linked list. This structure should hold
   your friends’ names and addresses.
   Because of the many possible solutions, answers are not provided for the following exer-
   cises.
   6.ON YOUR OWN:Write a program that declares a 12[ts]12 array of characters.
   Place X’s in every other element. Use a pointer to the array to print the values to
   the screen in a grid format.
   7.ON YOUR OWN:Write a program that uses pointers to type doublevariables to
   accept 10 numbers from the user, sort them, and print them to the screen. (Hint:
   See Listing 15.10.)
   8.ON YOUR OWN:Modify the program in exercise 7 to allow the user to specify
   whether the sort order is ascending or descending.

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