Structures:- A structure is a user-defined data type that allows you to group together different data types under a single name.
Functions:- Functions in C are blocks of code that perform a specific task. They allow you to break down your program into smaller, manageable pieces.

Declaring structure as function argument:
            Return_type  function_name(struct structure_name struct_var_name);
            

Examples :

Program.c

#include <stdio.h> // Define a structure named 'Rectangle' struct Rectangle { float length; float width; }; // Function declaration float calculateArea(struct Rectangle rect); int main() { // Declare and initialize a structure variable struct Rectangle myRectangle = {5.0, 3.0}; // Function call float area = calculateArea(myRectangle); // Display the result printf("Rectangle Area: %.2f\n", area); return 0; } // Function definition float calculateArea(struct Rectangle rect) { return rect.length * rect.width; }

Output:

        Rectangle Area: 15.00