Compiler lab2 UESTC

Environment

	System: Mac OS 10.15.1 (19B88)
	C compiler: Apple clang version 11.0.0 (clang-1100.0.33.12)
	flex: flex 2.5.35 Apple(flex-32)

	make rdcheck
	make rdparser
	./rdcheck [input] [output]
	./rdparser [input] [output]