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C - Structures

When programming, it is often convenient to have a single name with which to refer to a group of a related values. Structures provide a way of storing many different values in variables of potentially different types under the same name. This makes it a more modular program, which is easier to modify because its design makes things more compact. Structs are generally useful whenever a lot of data needs to be grouped together--for instance, they can be used to hold records from a database or to store information about contacts in an address book. In the contacts example, a struct could be used that would hold all of the information about a single contact--name, address, phone number, and so forth.

The format for defining a structure is

struct Tag {

For example:

struct example {
  int x;
struct example an_example; /* Treating it like a normal variable type
                            except with the addition of struct*/
an_example.x = 33;          /*How to access its members */
#include <stdio.h>

struct xampl {
  int x;

int main()
    struct xampl structure;
    struct xampl *ptr;

    structure.x = 12;
    ptr = &structure; /* Yes, you need the & when dealing with 
                           structures and using pointers to them*/
    printf( "%d\n", ptr->x );  /* The -> acts somewhat like the * when 
                                   does when it is used with pointers
                                    It says, get whatever is at that memory
                                   address Not "get what that memory address