                                            Assingment no .3
Aim: writing program on reading keystrokes from keboard.
Drawing filled area.
the GDI mapping mode.
Create a window with areaphics
# include <window.h>
//# indicates directive
//Directives are direct 
//Directive are direct instruction to the complire
//macro are also directives
//Directive are execucated before compilation
//include tells vc++ that the program has identifire defind in the header file.
LRESULT CALLBACK WNDPROS(HWND,UINT,WPARAM,LPARM);
//this is prototype decleration or forword declaraiton
//it is the first line of function defination with semicolan 
//yells vc++ to box for the function defination anywhere in the program
//Without prototype ;calling a function therefore before defination will result in function not defind compliler error
//wndproc function is defind after defination of winmain.  