Why do My C Code go Wrong - c

Question

The below is my code. Compiler generates the errors as
#include<stdio.h>
struct Shelf{
int clothes;
int *books;
};
struct Shelf b;
b.clothes=5;
*(b.books)=6;
Compiler generates the errors as below for both statements b.clothes=5; and b->books=6; in above code.
error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘->’ token
I'm not a beginner at C and I believe that what I have written is correct. Kindly solve my problem

Answer 1

FIRST
You cannot do this
struct Shelf{
int clothes;
int books;
};
struct Shelf b;
b.clothes=5;
b.books=6;
In global scope
You can assign value inside a function
int main (void )
{
b.clothes=5;
b.books=6;
}
Or initializing values on declaration
struct Shelf b = { .clothes = 5, .books = 6 };
Moreover as you can see b is not a pointer so using -> is not correct: use . to access members of struct.
SECOND
Your struct has a pointer member book
struct Shelf{
int clothes;
int *books;
};
What you can do is to set it to the address of another variable, like
int book = 6;
struct Shelf b = { .clothes = 5, .books = &book };
Or allocate memory for that pointer like
int main (void )
{
b.clothes=5;
b.books=malloc(sizeof(int));
if (b.books != NULL)
{
*(b.books) = 6;
}
}
BTW I guess you want an array of books, so
int main (void )
{
b.clothes=5;
b.books=malloc(sizeof(int) * MAX_N_OF_BOOKS);
if (b.books != NULL)
{
for (int i=0; i<MAX_N_OF_BOOKS; i++)
b.books[i] = 6;
}
}
COMPETE TEST CODE
#include <stdio.h>
#include <stdlib.h>
struct Shelf
{
int clothes;
int *books;
};
int main(void)
{
struct Shelf b;
b.clothes = 5;
b.books = malloc(sizeof(int));
if (b.books != NULL)
{
*(b.books) = 6;
}
printf ("clothes: %d\n", b.clothes);
printf ("book: %d\n", *(b.books) );
}
OUTPUT
clothes: 5
book: 6

Answer 2

b is a struct, not a pointer, so -> is not correct.
It's like doing (*b).books, which is wrong.
struct Shelf{
int clothes;
int *books;
};
One data member of the struct is a pointer, however:
struct Shelf b;
is not a pointer, it is just a struct as I said before.
As for your question in comment:
b.clothes=5;
is correct. Also something like this would be ok:
int number = 6;
b.books = &number;

Answer 3

-> operator used to access of member of struct via pointer. b is not dynamically allocated so b->books=6; is wrong. You should first allocate memory for member books and then dereference it.
b.books = malloc(sizeof(int));
*(b.books)= 6;