/in/foo.c: In function 'main':
/in/foo.c:71:3: warning: 'gets' is deprecated [-Wdeprecated-declarations]
   gets(a);
   ^~~~
In file included from /in/foo.c:34:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.c:67:12: warning: unused variable 'i' [-Wunused-variable]
  int c,d,n,i;
            ^
/in/foo.c:67:8: warning: unused variable 'd' [-Wunused-variable]
  int c,d,n,i;
        ^
/in/foo.c:67:6: warning: unused variable 'c' [-Wunused-variable]
  int c,d,n,i;
      ^
/tmp/cc3C83Rn.o: In function `main':
foo.c:(.text.startup+0x3b): warning: the `gets' function is dangerous and should not be used.