/in/foo.cc:5:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
main()
^
/in/foo.cc: In function 'int main()':
/in/foo.cc:8:28: warning: passing NULL to non-pointer argument 2 of 'void* memset(void*, int, size_t)' [-Wconversion-null]
memset(a,NULL,sizeof(char));
^
/in/foo.cc:9:2: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
gets(a);
^~~~
In file included from /usr/include/c++/6/cstdio:42:0,
from /usr/include/c++/6/ext/string_conversions.h:43,
from /usr/include/c++/6/bits/basic_string.h:5417,
from /usr/include/c++/6/string:52,
from /usr/include/c++/6/bits/locale_classes.h:40,
from /usr/include/c++/6/bits/ios_base.h:41,
from /usr/include/c++/6/ios:42,
from /usr/include/c++/6/ostream:38,
from /usr/include/c++/6/iostream:39,
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:9:8: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
gets(a);
^
In file included from /usr/include/c++/6/cstdio:42:0,
from /usr/include/c++/6/ext/string_conversions.h:43,
from /usr/include/c++/6/bits/basic_string.h:5417,
from /usr/include/c++/6/string:52,
from /usr/include/c++/6/bits/locale_classes.h:40,
from /usr/include/c++/6/bits/ios_base.h:41,
from /usr/include/c++/6/ios:42,
from /usr/include/c++/6/ostream:38,
from /usr/include/c++/6/iostream:39,
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:11:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
while(i<=strlen(a)-2)
~^~~~~~~~~~~~~
/in/foo.cc:28:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
while(i<=strlen(a)-2)
~^~~~~~~~~~~~~
/tmp/ccWFaPF7.o: In function `main':
foo.cc:(.text.startup+0x22): warning: the `gets' function is dangerous and should not be used.
