Thread: Help with C structures

I just learned about c structures the other day but I can't seem to get them to work. It give the wrong result at the end.
The warnings I'm getting are:
In function `main':
24 [Warning] comparison between pointer and integer
26 [Warning] assignment makes integer from pointer without a cast
27 [Warning] passing arg 1 of `strcpy' from incompatible pointer type
29 assignment makes integer from pointer without a cast

Code:

# include <stdio.h>
# include <stdlib.h>
# include <string.h>
struct student
{
       char name [50];
       char id [50];
       char score [50];
};

int main ()
{
    int i;
    char sum=0, high=0,avg, highest[50][50];
    struct student stu[i];
    for (i=0; i<=4; i++)
    {
        printf ("Enter the student's name.");
        scanf ("%s", &stu[i].name);
        printf ("Enter the student's ID.");
        scanf ("%s", &stu[i].id);
        printf ("Enter the student's score.");
        scanf ("%f", &stu[i].score);
        if (stu[i].score>high)
        {
           high = stu[i].score;
           strcpy (highest,stu[i].name);
        }
        sum = sum + stu[i].score;
    }
    avg = sum/5;
    printf ("Student %s got the highest grade of %f", highest, high); 
    system ("pause");
    return 0;
}

If you want score to be a floating-point number, then don't declare it as a char array.

Originally Posted by tabstop

If you want score to be a floating-point number, then don't declare it as a char array.

i get the same errors when i declare it as a float

No, the first two warnings will go away. For the last, if you want highest to be a string, then you don't need 50 strings of 50 characters each as you have it.

Originally Posted by tabstop

No, the first two warnings will go away. For the last, if you want highest to be a string, then you don't need 50 strings of 50 characters each as you have it.

I changed it to a float and now I'm getting the following errors.

25 invalid operands to binary >
27 incompatible types in assignment
30 invalid operands to binary +


I'm sorry if I'm just not getting this but I'm new at programming so please bare with me.

Code:

# include <stdio.h>
# include <stdlib.h>
# include <string.h>
struct student
{
       char name [50];
       char id [50];
       float score [50];
};

int main ()
{
    int i;
    float sum=0, high=0,avg;
    char highest[50];
    struct student stu[i];
    for (i=0; i<=4; i++)
    {
        printf ("Enter the student's name.");
        scanf ("%s", &stu[i].name);
        printf ("Enter the student's ID.");
        scanf ("%s", &stu[i].id);
        printf ("Enter the student's score.");
        scanf ("%f", &stu[i].score);
        if (stu[i].score>high)
        {
           high = stu[i].score;
           strcpy (highest,stu[i].name);
        }
        sum = sum + stu[i].score;
    }
    avg = sum/5;
    printf ("Student %s got the highest grade of %f", highest, high); 
    printf ("The average of all the scores are %f", avg);
    system ("pause");
    return 0;
}

Does each student have 50 scores?

Originally Posted by tabstop

Does each student have 50 scores?

Each student is suppose to have 1 score but the algorithm we got to work with set the array to 50.

No, you just typed [50] in because you weren't paying attention. Change it to float score; and be done with it.

Originally Posted by tabstop

No, you just typed [50] in because you weren't paying attention. Change it to float score; and be done with it.

The algorithm was done by a member of the class and the teacher approved of it so we just assumed it was correct but THANK YOU so much for all the help. It was very much appreciated.