Help with Structures

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January 26th, 2013, 01:18 PM

bass123

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Help with Structures

Currently I am working with structures, however I am not quite sure how to use the printf function after the input has been stored. Below is my code. Suggestions? Thanks in advance by the way

Code:

#include <stdio.h>

typedef struct
{
     char name[50];
     float grade[4];
     float aver;
     int pos;
}stud;

stud all[15];
stud read();
int a;

int main()
{
     for(a=0;a<15;a++)
     {
          stud[a]=read();
          printf("HELP HERE PLEASE");
}

January 26th, 2013, 01:21 PM

salem

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Something like
stud students[15];

Then
students[a] = read();

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January 26th, 2013, 02:03 PM

dwise1_aol

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You've created a new datatype called stud. You then declared an array, all, whose elements are of type stud.

This line
stud[a]=read();
makes no sense whatsoever. There is no array named "stud". There is, however, an array named "all", so you should be using it instead.

The syntax for accessing a field in a struct is this: <struct variable>.<fieldname>
So to access the aver field of the second struct in the array, you would write this: all[1].aver

January 26th, 2013, 08:56 PM

bass123

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Thanks for the help. I have on final question. I dont want to type in all the data when it comes to doing a test run of my program. Is it possible to read all of the input from a text file?

January 27th, 2013, 12:37 AM

salem

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Of course you can read input from a file.

scanf("%d", &num);
can be written as
fscanf(stdin,"%d", &num);

From there, it's just a small step to
FILE *fp = fopen("data.txt","r");
fscanf(fp,"%d", &num);

January 27th, 2013, 02:58 AM

clifford

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Quote:

Originally Posted by bass123

I dont want to type in all the data when it comes to doing a test run of my program. Is it possible to read all of the input from a text file?

If your manual input is via stdin (i.e. you are using standardio functions such as getchar() etc.), then you can use redirection to take input from a file rather than manual input. So for example if you have a file grades.dat containing:

Joe Bloggs
14
Sam Spoon
23
Jane Doe
24
John Doe
20

And a program called grades.exe, you can redirect the file to stdin thus:

grades <grades.dat

and the data will be input as if you had typed it from the keyboard.

This approach means that you can write the code for manual input but test with a file rather than specifically writing it for file access as suggested by Salem. The choice would depend on your requirements.

January 28th, 2013, 04:33 AM

links123

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structure problem

This is meaningful way:

stud all[15];

all[0].aver=18;
all[1].aver=28;
all[2].aver=45;

all[0].name="Collingam";

Help with Structures

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