/in/foo.cc: In function 'int main()':
/in/foo.cc:20:2: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets (st[1] + 1);
  ^~~~
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /in/foo.cc:1:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:20:17: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets (st[1] + 1);
                 ^
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /in/foo.cc:1:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:22:3: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   gets (st[i] + 1);
   ^~~~
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /in/foo.cc:1:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:22:18: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   gets (st[i] + 1);
                  ^
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /in/foo.cc:1:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:27:3: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   gets (st[n * 2 - i + 1] + 1);
   ^~~~
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /in/foo.cc:1:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:27:30: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   gets (st[n * 2 - i + 1] + 1);
                              ^
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /in/foo.cc:1:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/tmp/cc6rstyE.o: In function `main':
foo.cc:(.text.startup+0x2b): warning: the `gets' function is dangerous and should not be used.