what is difference between structure and classes

Answer 1

A struct is syntactically similar to a class and both create a class type. In the C language a struct can contain only data memebers but this limitation does not apply to C++. In C++ the struct is essentially just an alternative way to specify a class. In fact, in C++ the only difference between a class and a struct is that by default all members are public in a struct and private in a class. In all other aspects structures and classes are equivalent.

Answer 2

structures do allow that. First declare a class add data and functions and then change the keyword class to struct. It will still work

Answer 3

classes let you declare functions in them as well as let you define who can access these functions and member variables. structures don't