Create a C program: to reinforce the fact that knowing how to

manipulate an array boils down to knowing how to manipulate the

array's indices. The program will use an array as a lookup table

which means that a required value is stored and retrieved from the

table by specifying the index where the value is to be stored or

retrieved from. For example, the following table represents an array

of $5$ floats. Each float refers to a GPA of a student where the GPA is

stored at some index i such that i$+1$ refers to the ID of the student

with that GPA. Note that currently, students with IDs $2$ and $5$ are the

only ones with GPAs. $[$Student with ID $2$ is at position $1$ in the array

and the one with ID $5$ is at position $4$ in the array.$]$The program will be designed so that it contains functions that you

will write. ALL function bodies are to be written BELOW the main

function but the prototypes for those functions must be written just

above the main.

Type in the following definition of a preprocessor constant above the

main:

#define MAX$\_$STUDENTS $5$

This will allow you to use the name MAX$\_$STUDENTS anywhere you need to

use the constant $5$ when referring to the number of students.

Function prototypes:

int menu$()$;

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void processChoice$($int choice, float gpas$[])$;

void addGPA$($float gpas$[])$;

void removeGPA$($float gpas$[])$;

int countStudents$($float gpas$[])$;

float calcAvgGPA$($float gpas$[])$;

void displayGPAs$($float gpas$[])$;

The algorithm for the main function follows: $($Pay attention to

indentation in the algorithm.$)$

Declare a float array named gpas of size MAX$\_$STUDENTS and set

all its contents to $0.$

Declare an integer variable named choice.

Start a do$/$while loop as follows.

do:

Call a function named menu and collect what it returns in

the variable called choice. The function does not take any

parameters.

Call a function named processChoice and pass it the choice

and the array in that order. This function does not return

anything.

while choice is not equal to $6.$

The algorithm for the menu function follows:

Declare an integer variable named ch$.($ch stands for choice.$)$

Present the user with the following menu:

$1)$ Add a student's GPA.

$2)$ Remove a student's GPA.

$3)$ Count number of students.

$4)$ Display GPA data.

$5)$ Calculate average GPA.

$6)$ Quit

Collect the choice from the user in the variable named ch$.$

Return ch$.$

The algorithm for the processChoice function follows:

Use a switch statement to determine what choice was passed into

the function:

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Case $1$: call the addGPA function and pass it the gpas

array.

Case $2$: call the removeGPA function and pass it the gpas

array.

Case $3$: call the countStudents function and pass it the

gpas array. Collect what the function returns in an

integer variable and print the contents of that variable

with a nice, relevant message.

Case $4$: call the displayGPAs function and give it the gpas

array.

Case $5$: call the calcAvgGPA function and pass it the gpas

array. Collect what the function returns in a float

variable and print the contents of that variable with a

nice, relevant message.

Case $6$: print "Bye!"

Default: print a message stating that the choice was

invalid.

The algorithm for the addGPA function follows:

This function should ask for an integer ID from the user with

values from $1$ to MAX$\_$STUDENTS.

If the user gives a value outside of the range, the function

should print an appropriate error message and then return.

Otherwise, the function should do the following:

Reduce the value of the ID entered by $1.$

Check to see if the gpas array at the index referred to by

ID is $0.$ If it is$,$ then the function should do:

Ask for a gpa between $0$ and $4$ and keep asking until

it gets a valid gpa.

Once the function gets a valid gpa, it should then

assign the new gpa to the position in the gpas array

as indexed by the ID$.$

Else $($that position in gpas is already taken$)$ so print a

message stating that the student already has a gpa.

The algorithm for the removeGPA function follows:

This function should ask for an integer ID from the user with

values from $1$ to MAX$\_$STUDENTS.

If the user gives a value outside of the range, the function

should print an appropriate error message and then return.

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Otherwise, the function should do:

Reduce the value of the ID entered by $1.$

Assign $0$ to the position of the gpas array indexed by ID$.$

The description of the countStudents function follows:

The function should count the number of non$-$zero entries in the

array and return the count. Use a for loop to run down the

array up to$,$ but not including MAX$\_$STUDENTS.

The description of the displayGPAs function follows:

The function should display a header row with the words

"Student ID$"$ and "GPA" in two neat columns. Then the function

should use a for loop to run down the array up to$,$ but not

including MAX$\_$STUDENTS. Within the loop, the function should

print the student IDs and corresponding GPAs neatly under the

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