Assessment Tool

Lecture 13: Pointer Parameters

Content Tested: Pointers

Lecture Content:

Function parameters
Call by value
Pointer parameters
Call by reference
Pointer types

Goals:

Learn concepts and theories
Develop capacity to think for oneself
Develop ability to apply principles and generalizations already learned to new problems and situations
Develop ability to think creatively

Assessment Technique: Application Cards

Purpose:

To allow instructors to find out if students understand the need and use for pointer parameters.

Activity:

We have just seen the syntax and purpose for using pointer parameters. Name three functions for which you would use pointer parameters. For this activity, please describe the following: 1) function name, 2) function parameters, 3) function description, 4) return values. Please indicate which parameters are pointer parameters. You do not need to write C code for this activity -- just descriptions of the functions.

You may want to think about previous homework assignments. Where would you use pointer parameters?

Possible Solution:

function: sortThree
function parameters: 3 pointers to ints (*a, *b, *c)
function description: This function takes three pointers to ints and sorts them so that a points to the smallest value, b points to the middle value, and c points to the largest value.
return values: None

Possible Uses of Activity:

Have students work on the activity individually and then get into small groups to explain their functions to one another.
Have students work on the activity in small groups and have each group present their functions to the class.
Be sure to address why pointer parameters are necessary and useful. If some functions can be easily written without pointer parameters, point this out to the students. Also, you might try to come up with call-by-value solutions to functions using pointer parameters. For example, instead of using sortThree, a programmer could write the functions findMin, findMiddle, and findMax and use the return values of these to assign to a, b, and c.