Write a class result that has array of three integers as attribute. It has a member function to input and a member function to display average of elements. Create another class student that contains...

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Extracted text: Write a class result that has array of three integers as attribute. It has a member function to input and a member function to display average of elements. Create another class student that contains object of class result. It has additional attributes of roll number and name. It also has member functions to input and display data members.