foo.cc: In function 'int main()':
foo.cc:15:13: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   15 |         gets(bookname);
      |         ~~~~^~~~~~~~~~
In file included from /nix/store/42izybv2fz3ps5pcg3dvcmn85pc9406y-gcc-11.3.0/include/c++/11.3.0/cstdio:42,
                 from /nix/store/42izybv2fz3ps5pcg3dvcmn85pc9406y-gcc-11.3.0/include/c++/11.3.0/ext/string_conversions.h:43,
                 from /nix/store/42izybv2fz3ps5pcg3dvcmn85pc9406y-gcc-11.3.0/include/c++/11.3.0/bits/basic_string.h:6608,
                 from /nix/store/42izybv2fz3ps5pcg3dvcmn85pc9406y-gcc-11.3.0/include/c++/11.3.0/string:55,
                 from /nix/store/42izybv2fz3ps5pcg3dvcmn85pc9406y-gcc-11.3.0/include/c++/11.3.0/bits/locale_classes.h:40,
                 from /nix/store/42izybv2fz3ps5pcg3dvcmn85pc9406y-gcc-11.3.0/include/c++/11.3.0/bits/ios_base.h:41,
                 from /nix/store/42izybv2fz3ps5pcg3dvcmn85pc9406y-gcc-11.3.0/include/c++/11.3.0/ios:42,
                 from /nix/store/42izybv2fz3ps5pcg3dvcmn85pc9406y-gcc-11.3.0/include/c++/11.3.0/ostream:38,
                 from iostream:39:
/nix/store/ck17nf5q2m51d9jpkpsirx91s64vh202-glibc-2.35-163-dev/include/stdio.h:605:14: note: declared here
  605 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
/nix/store/dpxy5cr7cm0nch0qvq2qygs9jwnmhiy5-binutils-2.38/bin/ld: /tmp/ccQAMkP2.o: in function `main':
foo.cc:(.text.startup+0x57): warning: the `gets' function is dangerous and should not be used.

正在同步测试数据，请稍后
Found 10 testcases.
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