“A:class type redefinition” error in C++

The error “class type redefinition” typically means that you have multiple definitions of the same class in your code, which can cause conflicts and errors.

This error can occur if you have included the header file for class A in both A.cpp and B.cpp, or if you have included it multiple times in B.cpp. When the compiler tries to compile the code, it encounters conflicting definitions of class A and throws an error.

To fix this error, you should ensure that you only have one definition of class A in your code. One common way to do this is to use header guards in your header files to prevent multiple definitions. For example, you can add the following lines at the beginning and end of your A.h file:

#ifndef A_H
#define A_H

// class A definition here

#endif

This ensures that the code inside the header guard is only included once in your program, even if the header file is included in multiple source files.