Can we declare function inside structure of C Programming?

No, in C programming, you cannot declare a function inside a structure. A structure in C is a user-defined data type that allows you to combine data items of different kinds. Structures are used to represent a record, and they can store data of different types, such as int, char, float, etc. However, they cannot contain functions.

Here is an example of a structure in C:

struct Student {
   char name[50];
   int roll;
   float marks;
};

In this example, the structure Student has three members: name (string), roll (integer), and marks (float). But you cannot declare a function inside this structure.

If you want to associate functions with your structures, you might want to look into C++ which has a feature called classes. Classes are an expanded concept of data structures: like data structures, they can contain data members, but they can also contain functions as members.