/in/foo.cc: In function 'int main()':
/in/foo.cc:10:2: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets (stra) ;
  ^~~~
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:46,
                 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:10:12: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets (stra) ;
            ^
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:46,
                 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:11:2: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets (strb) ;
  ^~~~
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:46,
                 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:11:12: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets (strb) ;
            ^
In file included from /usr/include/c++/6/cstdio:42:0,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:46,
                 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:14:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for ( int i = 0 ; i < strlen (stra) ; i++)
                    ~~^~~~~~~~~~~~~~~
/in/foo.cc:18:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for ( int i = 0 ; i < strlen (stra) ; i ++)
                     ~~^~~~~~~~~~~~~~~
/in/foo.cc:21:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
      for ( int i = 0 ; i < strlen (stra) ; i ++)
                        ~~^~~~~~~~~~~~~~~
/in/foo.cc:28:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if (head == strlen (strb))
        ~~~~~^~~~~~~~~~~~~~~~
/in/foo.cc:29:9: warning: statement has no effect [-Wunused-value]
    head == 0;
    ~~~~~^~~~
/in/foo.cc:41:11: warning: statement has no effect [-Wunused-value]
       ans == 0;
       ~~~~^~~~
/tmp/ccSNEIFD.o: In function `main':
foo.cc:(.text.startup+0x20): warning: the `gets' function is dangerous and should not be used.