/in/foo.cc: In function 'int main()':
/in/foo.cc:13:2: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
gets(s2);
^~~~
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:13:9: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
gets(s2);
^
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:10:6: warning: variable 'a' set but not used [-Wunused-but-set-variable]
int a[N],i=0,k=0;
^
/tmp/ccVPW6AY.o: In function `main':
foo.cc:(.text.startup+0xc): warning: the `gets' function is dangerous and should not be used.