（5.3）图遍历
.............\Debug
.............\.....\G1.exe
.............\.....\G1.ilk
.............\.....\G1.obj
.............\.....\G1.pdb
.............\.....\Graph.ilk
.............\.....\Graph.obj
.............\.....\Graph.pdb
.............\.....\vc60.idb
.............\.....\vc60.pdb
.............\G1.CPP
.............\G1.DSP
.............\G1.DSW
.............\G1.ncb
.............\G1.OPT
.............\G1.PLG
.............\Graph.dsp
.............\Graph.dsw
.............\Graph.ncb
.............\Graph.opt
.............\Graph.plg