绘制图形
........\1.dat
........\2.txt
........\Debug
........\.....\lesson2.exe
........\.....\lesson2.ilk
........\.....\lesson2.obj
........\.....\lesson2.pch
........\.....\lesson2.pdb
........\.....\vc60.idb
........\.....\vc60.pdb
........\Lesson2.cpp
........\Lesson2.dsp
........\Lesson2.dsw
........\Lesson2.exe
........\Lesson2.ncb
........\Lesson2.opt
........\lesson2.plg
........\NeHe's Readme.txt