Please do in cpp

Invert String Case [10 points) Write a function in your header file, with the following signature: std::string transform_case( std::string ) which inverts the case of the input string and returns the result. Inverting the case means, transforming uppercase letters into lowercase letters, and vice-versa, with the exception of the letter 'E', which should always be in uppercase, and the letter 'A', which should always be unmodified. Example: "Hello World" transforms to "HELLO WORLD", and "Alphabet" transforms to "ALPHABET", and "Earth" transforms to "EaRTH