You will use the following Shape interface to implement a Circle, Triangle, and Rectangle classes. Among the method(s) required by the interface...Circles have a radiusTriangle have a base and heightRectangle have a length and a widthYou will be passed a file name contain shape data from the command line. Some kind of Executive class should read the file and use a ShapeContainer (see below) to store pointers to various shapes, using the specifications for each shape given in the file. The file also contains commands to print the area of a given shape and to exit the program. When a print command is issued, the information about the shape and it's area should be printed. Shape InterfaceYou may NOT add any public methods to this class.#include class Shape{ public: virtual double area() const = 0; virtual std::string shapeName() const = 0; virtual ~Shape() {}};ShapeContainerYou may NOT add any public methods to this class#include "Shape. h"#include class ShapeContainer{ public: ShapeContainer(int size); //initialize pointers in m_arrayOfShapes to nullptr ~ShapeContainer(); double area(int index) const; //throws a std::runtime_error if index is invalid, meaning out of range OR index has nullptr std::string shapeName(index) const; //throws a std::runtime_error if index is invalid, meaning out of range OR index has nullptr void add(Shape* shapePtr, int index); //throws a std::runtime_error if index is invalid OR if shapePtr is nullptr void remove(int index); //throws a std::runtime_error if the index is invalid OR there is no object to delete private: Shape** m_arrayOfShapes; int m_size;}File FormatThe first item in the file will be the size of the shape container, which cannot change despite how many adds are in the file. Following that will be lines containing one of the three following commands in any order:ADDis the index in the container to put the shapewill be CIR, TRI, or REC for Circle, Triangle, and Rectangle respectivelywill the be radius, base and height, or length and width, of a Circle, Triangle, or Rectangle the shape at a given indexThe index may be out of range or not yet set, in which case you must catch and handle the exception to gracefully recover and continue onPRINTPrints the name and area of the shape at a given index, as shown belowThe index may be out of range or not yet set, in which case you must catch and handle the exception to gracefully recover and continue onEXITEnds the program5ADD 0 CIR 5.5ADD 1 TRI 2.5 6.6PRINT 0ADD 2 REC 10.5 20.25PRINT 99PRINT 2 EXITSample run:Shape at index 0: Circle area = 95.0331Shape at index 99: Does not existShape at index 2: Rectangle area = 212.625Exiting...