useful.o: /mit/lens/src/working/ansi-include/assert.h
useful.o: /mit/lens/src/working/ansi-include/stddef.h
useful.o: /mit/lens/src/working/ansi-include/stddef.h
useful.o: /mit/lens/src/working/ansi-include/stddef.h
useful.o: /mit/lens/src/working/ansi-include/stdio.h
useful.o: /mit/lens/src/working/ansi-include/stdlib.h
useful.o: /mit/lens/src/working/include/sysdep.h
useful.o: /usr/include/ctype.h
useful.o: /usr/include/stdio.h
useful.o: /usr/include/sys/types.h
useful.o: useful.c