递归遍历\Debug\tree.exe
........\.....\tree.ilk
........\.....\tree.obj
........\.....\tree.pch
........\.....\tree.pdb
........\.....\vc60.idb
........\.....\vc60.pdb
........\tree.cpp
........\tree.dsp
........\tree.dsw
........\tree.ncb
........\tree.opt
........\Debug
递归遍历