In file included from /usr/include/c++/6/backward/hash_map:60:0,
                 from /in/foo.cc:3:
/usr/include/c++/6/backward/backward_warning.h:32:2: warning: #warning This file includes at least one deprecated or antiquated header which may be removed without further notice at a future date. Please use a non-deprecated interface with equivalent functionality instead. For a listing of replacement headers and interfaces, consult the file backward_warning.h. To disable this warning use -Wno-deprecated. [-Wcpp]
 #warning \
  ^~~~~~~
/in/foo.cc: In function 'PV* get_hash_id(GMap*, char*, unsigned int, int)':
/in/foo.cc:54:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if(pv->encodeValue == encodeValue) {
            ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:117:9: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
         gets(buffer);
         ^~~~
In file included from /in/foo.cc:2:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:117:20: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
         gets(buffer);
                    ^
In file included from /in/foo.cc:2:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:122:9: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
         gets(buffer);
         ^~~~
In file included from /in/foo.cc:2:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:122:20: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
         gets(buffer);
                    ^
In file included from /in/foo.cc:2:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:178:58: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
             if(prefix_len == 0 || prefix[k] == d_cArr[j] && ++k) {
                                   ~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
/tmp/ccO26q6k.o: In function `main':
foo.cc:(.text.startup+0xd2): warning: the `gets' function is dangerous and should not be used.