If there are three files. main.c and head2.h, head3.h.
head3.h has been imported into head2.h already. And in main.c
So head3.h has been imported twice in main.c(in main.c and in head2.h), do you think that variable defined in head3.h would cause some unexpected failure, and should I avoid such manner?Code:#include "head3.h" #include "head2.h" ................