Thread: Modules

I'm a beginner and don't know how to use modules. So I have a task :

Code:

Write a main() program that prints a monthly sales report.  This report will list the sales for each store the company owns and the total sales.  To do this it must first call a module / function that takes in the sales for each store.  The sales should be stored in an array of the appropriate data type (assume the dollar value of sales can be really big).  Since there are only 3 stores, the array only needs to store 3 values.  This array is initialised in main(), and any data entered in other module(s) must be stored in that array.  This CANNOT be done using global scope, you must pass the array to the module(s).

What I wrote :

Code:

#include <stdio.h>


main()
{


        float balance[3];/* the array*/
        int i;


        for (i = 0; i < 3;)
        {
                i = i + 1;
                printf("Enter sales amount for store #%d\n",i);
                scanf("%f",&balance[i-1]);


        }


        printf("MONTHY SALES REPORT (BY STORE NUMBER):\n");
        printf("Store #1 $ %f\n",balance[0] );
        printf("Store #2 $ %f\n",balance[1] );
        printf("Store #3 $ %f\n",balance[2] );
}

What I've tried to do

Code:

#include <stdio.h>


int ILikeCats(float balance[3])
{  
      for (i = 0; i < 3;)
        {
                i = i + 1;
                printf("Enter sales amount for store #%d\n",i);
                scanf("%f",&balance[i-1]);


        } 
}
main()
{


        float balance[3];/* the array*/


        ILikeCats(float balance[3]);


        printf("MONTHY SALES REPORT (BY STORE NUMBER):\n");
        printf("Store #1 $ %f\n",balance[0] );
        printf("Store #2 $ %f\n",balance[1] );
        printf("Store #3 $ %f\n",balance[2] );
}

Could you help and explain it? Thanks in advance!

Originally Posted by Salem

> ILikeCats(float balance[3]);
Just say
ILikeCats(balance);

Thanks for the speedy reply! I did as you said but it gives me the error in 21st line where the array begins.

Code:

array.c: In function ‘main’:
array.c:21:11: error: expected expression before ‘float’

The full code.

Code:

#include <stdio.h>




float ILikeCats(float balance[3])
{
       int i = 0;
        for (i = 0; i < 3;)
        {
        i = i + 1;
        printf("Enter sales amount for store #%d\n",i);
        scanf("%f",&balance[i-1]);


        }
}
main()
{


float balance[3];/* the array*/




ILikeCats(float balance);




printf("MONTHY SALES REPORT (BY STORE NUMBER):\n");
printf("Store #1 $ %f\n",balance[0] );
printf("Store #2 $ %f\n",balance[1] );
printf("Store #3 $ %f\n",balance[2] );
}
~

For me it seems okay and it should work; however it doesnt work >.>.

Code:

ILikeCats(float balance);

Look very carefully at what Salem wrote. Because it wasn't this.

In post # 3, look at line 9 - it has a semicolon - what is the reason for it?

Originally Posted by PaulS

In post # 3, look at line 9 - it has a semicolon - what is the reason for it?

Are you referring to this line?

Code:

for (i = 0; i < 3;)

If so, that's standard syntax for the "for()" (the "update" portion is blank, since it's done within the loop body instead ... for some reason).

OK, I see that- I guess I am not advanced enough to understand why or if it would affect the remaining code.

All parts of the "for()" loop are technically optional.

In fact, one of the accepted ways of writing an infinite loop is:

Code:

for( ; ; )

Note that while the parts might be optional, the semi-colons are not.

I have the concept down - I guess I don't see an advantage to using it. Thanks for increasing my knowledge.

Originally Posted by Matticus

Code:

ILikeCats(float balance);

Look very carefully at what Salem wrote. Because it wasn't this.

Oh yeah! That's true;I made a mistake. Thank you. It works now!