Structuring Data with Pointers: A Deep Dive into Structures and Unions in C

Hey there, fellow coders! ? Structures and unions are like the building blocks of data in C. Today, we’re going to see how pointers act as the glue, binding these blocks to form intricate data structures. Ready to structure your understanding? Let’s lay the first brick!

Structures in C: The Organized Containers

Think of structures as customizable data containers. Unlike arrays which store similar data types, structures can house varied data types.

Pointers in the Realm of Structures

Pointers can point to structures, allowing dynamic allocation, efficient data manipulation, and more.

typedef struct {
    int id;
    char name[50];
} Student;

Student *s1 = (Student *)malloc(sizeof(Student));
s1->id = 101;
strcpy(s1->name, "Alex");

Code Explanation:

• We define a Student structure with an integer id and a character array name.
• We then dynamically allocate memory for a Student object and use a pointer s1 to refer to it.
• The -> operator allows us to access the structure’s members using the pointer.

Unions in C: The Space Savers

Unions are similar to structures, but with a twist! They allow multiple members but only one can contain a value at any given time, making them memory efficient.

Pointers Dancing with Unions

Just like structures, pointers can also point to unions, enabling dynamic memory operations.

typedef union {
    int marks;
    char grade;
} Result;

Result *r1 = (Result *)malloc(sizeof(Result));
r1->grade = 'A';

Code Explanation:

• We define a Result union which can store either marks as an integer or grade as a character.
• Memory is allocated for a Result object, and a pointer r1 points to it.
• We then store a grade in the union using the pointer.

Pointers, Structures, and Unions: When They Collaborate

Combining pointers with structures and unions can lead to intricate data constructs like linked lists, trees, and graphs. For instance, a linked list node can be a structure containing data and a pointer to the next node.

Wrapping Up: Pointers, The Architects of Data

Structures and unions lay the foundation, and pointers erect the edifice, giving shape to data in C. By mastering pointers with structures and unions, you can design intricate, efficient, and scalable data systems.