C Structure

Syntax

struct [structure tag] {
   member definition;
   member definition;
   ...
} [one or more structure variables];

Example

#include <stdio.h>
#include <string.h>

// Declare a structure with members
struct Person {
  char name[50];
  int age;
};

int main() {
  // Declare and initialize structure variable
  struct Person person1;
  strcpy(person1.name, "John Doe");
  person1.age = 35;

  // Print structure members
  printf("Person Name: %s\n", person1.name);
  printf("Person Age: %d\n", person1.age);

  return 0;
}

Output

The output of the above example will be:

Person Name: John Doe
Person Age: 35

Explanation

In C, a structure is a user-defined composite data type that groups together related data items of different types. A structure can contain variables, arrays, and other structures as its members. It is defined using the struct keyword followed by the structure tag and a set of member definitions.

Use

Structures are widely used in C for the following purposes:

• Storing related data items together
• Passing a collection of data items as a single argument to a function
• Representing complex data structures, such as trees and graphs
• Creating data types that can be easily customized and extended

Important Points

• A structure is a user-defined composite data type in C.
• The struct keyword is used to define a structure.
• A structure can contain variables, arrays, and other structures as its members.
• A structure can have one or more variables of its type.
• Structure members can be accessed using the dot (.) operator.
• Structure variables can be initialized using the curly braces ({}) syntax.
• To declare a structure variable, the structure tag must be followed by the variable name, separated by a space.

Summary

A structure in C is a user-defined composite data type that can group together related data items of different types. It can be used for storing related data items together, passing a collection of data items as a single argument to a function, representing complex data structures, and creating custom data types. Understanding the syntax and use cases for structures can greatly enhance the readability, functionality, and flexibility of your C programs.