typedef a = enum();typedef b = enum(x);typedef c = enum(x,y);typedef d = enum(x,y,);typedef e = enum(x=10, y);typedef f = int enum();typedef g = int enum(x,y);typedef h = int enum(x=10,y);typedef i = (int x,int y) enum( left=(-1,0), right=(1,0), up=(0,-1), down=(0,1));typedef j = enum(x,y);