Overview of Graphics System

    There are many new graphics functions in C++. They are all in the
    library, GRAPHICS.LIB.  These functions allow you to control the
    graphics system, manipulate screens and viewports, output text to the
    graphics screen, draw and fill shapes, control the background and
    foreground color, handle graphics errors and inquire into the state of
    the graphics system.

    In order to use these graphics functions, you must
     (1) include <graphics.h> in your program,
     (2) initialize the graphics system and put it in the
            graphics mode,
     (3) shut down the graphics system.

    Therefore, programs using graphics functions should have the
    following as a basic framework:

     #include <graphics.h>

     main()
          {
               int graphdriver = DETECT, graphmode;

               initgraph();

               /* graphics functions */

               closegraph();
          }