Nested structures in c is a structure within structure.We can declare one structure inside the another structure in the same way structure members also declared inside structure.

Example:-
          1)For example two structures one is College (outer structure)another is student(inner strcuture).
          2)College has some data members like college_id,college_code,college_name.
          3)Student has some data members like student_pin,student_name,student_age etc..
          4)The student structure is nested within the college structure 

          Struct College
{
	Data_member1;
	Data_member2;
	Struct Student
	{
		Data_member1;
		Data_member2;
};
};

Syntax for accessing the data members of nested structure:
Outer_structure_var_name.Inner_structure_var_name.data_member

          

Examples :

Program.c

#include <stdio.h> // Define outer structure with nested structure struct Person { char name[50]; int age; // Define inner structure struct Address { char street[50]; char city[50]; char state[20]; }address; //declaring structure variable for nested structure }; int main() { // Declare a structure variable struct Person person1; // Input information for the person printf("Enter name: "); scanf("%s", person1.name); printf("Enter age: "); scanf("%d", &person1.age); printf("Enter street: "); scanf("%s", person1.address.street); printf("Enter city: "); scanf("%s", person1.address.city); printf("Enter state: "); scanf("%s", person1.address.state); // Display the entered information printf("\nPerson Information:\n"); printf("Name: %s\n", person1.name); printf("Age: %d\n", person1.age); printf("Address: %s, %s, %s\n", person1.address.street, person1.address.city, person1.address.state); return 0; }

Output:

        Enter name: Cprogram
        Enter age: 34
        Enter street: Belllabaratories
        Enter city: america
        Enter state: america
        
        Person Information:
        Name: Cprogram
        Age: 34
        Address: Belllabaratories, america, america