c51teachcode ............\c ............\.\1.c ............\.\10.c ............\.\11.c ............\.\13-1.c ............\.\13-2.c ............\.\13-3.c ............\.\13-4.c ............\.\14.c ............\.\15.c ............\.\16.c ............\.\17.c ............\.\2.c ............\.\3.c ............\.\4.c ............\.\5.c ............\.\7-1.c ............\.\7-2.c ............\.\8.c ............\.\9-1.c ............\.\9-2.c