c++ programming

Class Grid contains a private 60×24 (60 wide and 24 high) grid of characters (a 2D array of char).  Initially the grid will be initialized so that all characters are spaces (this is done in Grid’s only constructor Grid()).  Class Grid must provide a set function so that the shapes can set  individual characters in the grid.  This function could have the prototype: void Grid::set(int x, int y, char c).  If the (x,y) values are inside the grid, set the (x,y) character in the grid to character c.  If the (x,y) values are outside the grid, do nothing.  

Class Grid must also provide a print function:  void Grid::print().  This function must draw the grid to standard output.  Grid::print() should first draw all the characters in row 0 followed by an endl.  Then all the characters in row 1 followed by an endl.  And so on.

Class Shape must be used as the base class for classes Square, Triangle, Circle, and Point.  It must store the x and y location that the shape is to be drawn (I called the variables m_x and m_y). It will have a single constructor that takes x and y as arguments.  In addition to the constructor, it will have a single member function draw() that must have a single argument, a reference to a Grid object (void draw(Grid &grid)).  This function must be a pure virtual function (learn this term, it will be on the next exam).

You can make a virtual function into a pure virtual function by assigning it to zero in the base class declarations: