/in/foo.c: In function 'Length':
/in/foo.c:6:2: warning: 'gets' is deprecated [-Wdeprecated-declarations]
  gets(s);
  ^~~~
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: In function 'main':
/in/foo.c:14:5: 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:15:2: 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: In function 'Length':
/in/foo.c:7:12: warning: 'i' is used uninitialized in this function [-Wuninitialized]
     while(s[i]!=0)
            ^
/in/foo.c: In function 'main':
/in/foo.c:7:12: warning: 'i' is used uninitialized in this function [-Wuninitialized]
     while(s[i]!=0)
            ^
/in/foo.c:5:6: note: 'i' was declared here
  int i;
      ^
/in/foo.c:7:12: warning: 'i' is used uninitialized in this function [-Wuninitialized]
     while(s[i]!=0)
            ^
/in/foo.c:5:6: note: 'i' was declared here
  int i;
      ^
/tmp/ccl7bjUc.o: In function `Length':
foo.c:(.text+0x5): warning: the `gets' function is dangerous and should not be used.