Thread: Task 7.4, help

Originally Posted by Franksy

1. Declare a structure which contains minimum two elements

Looks like you did that with struct petdataa.

Originally Posted by Franksy

2. in main function declair a local variable of the structure

You kinda did that, but not exactly. I would have expected:

Code:

struct petdataa petdata;

rather than an array.

Originally Posted by Franksy

3. read in the values for the structure elements (use scanf)

It looks like you did that in main, but with a small mistake: &petdata[i].name should have been petdata[i].name because an array is converted to a pointer to its first element in this context.

Originally Posted by Franksy

4. call a function print_data passing the local structure variable

You're supposed to pass the "local structure variable", or more likely a pointer to that. I would expect:

Code:

void print_data(struct petdataa petdata);

or more typically:

Code:

void print_data(const struct petdataa *petdata);

Code:

#include <stdio.h>
#include <stdlib.h>

/*
 * 1. Declare a structure which contains minimum two elements
 * 2. in main function declair a local variable of the structure
 * 3. read in the values for the structure elements (use scanf)
 * 4. call a function print_data passing the local structure variable
 * 5. print the values of the structure in the print_data
*/

struct petdataa
{
    int idtag;
    char name[20];
    float weight;
};

//does not matter what you called your struct varitable name
//in main. as you see in your function you can "rename" it.
//just need to use the names in your prams now
//to reference it.

//it knows what to use because of your "data type"
//using the struct you declared name.

// size_t is for taking care of whatever data type that
//system uses for the way it is being called.
// long int etc...
//
void print_data(struct petdataa DATA[], size_t amout)
{
    size_t count = 0;
    
    while (count < amout)
    {
        printf("Name %s ID %d Weight %.02f\n", DATA[count].name,DATA[count].idtag,
                                                DATA[count].weight);
        count++;
    }
}

int main()
{
        
    int count = 0, amount = 0;
    
    // bonus code
    
    printf("Enter amount of records you want to fill in\n");
    scanf(" %d", &amount);
    
    
    //struct petdataa petdata[2];
    // creates the array the size told at 
    //run time.
    
    struct petdataa petdata[amount];

    while ( count < amount )
    {
        printf("Enter a name, ID number and a weight in float notation.\n");
    
    
        scanf(" %19s %d %f", petdata[count].name, &petdata[count].idtag,
                            &petdata[count].weight);
        count++;
    }
    
    //pass your entire struct into your function, 
    //that is where your data values are at.
    //
    //you, the programmer already know what this
    //function is going to be used for, 
    //it is you that is writing it 
    //for your use in your program.
    //so use that to your advantage.
    
    print_data(petdata, sizeof(petdata)/sizeof(petdata[0]) );     
    
    return 0;
}

Do not use strcpy here: the original would have been correct once the address-of operator was removed, although the %s should have been changed to %19s to avoid buffer overflow. In fact, calling strcpy(petdata.name, name) leads to undefined behaviour because name was not initialised.

I;ve always an into issues using direct assignment of a char array. let e go check that over and give it a try, ( again) scanf is not one of my favorite functions. before time runs out to fix it in here.

Ok I stand corrected, now I am trying to remember where that issue was when I have it. Because that is the "fix" for that.ha

and thanks for that reminder about size declarations in scanf..