/in/foo.c: In function 'main':
/in/foo.c:9:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
  gets(s1);
  ^~~~
In file included from /in/foo.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.c:10:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
  gets(s2);
  ^~~~
In file included from /in/foo.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.c:6:6: warning: unused variable 'i' [-Wunused-variable]
  int i,n1,n2;
      ^
/in/foo.c: At top level:
/in/foo.c:15:2: error: expected identifier or '(' before numeric constant
 }1
  ^