foo.cc: In function 'int main()':
foo.cc:26:13: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   26 |         gets(a);int n = strlen(a);
      |         ~~~~^~~
In file included from /nix/store/h5kvfrjmpw792v8jg7nrzfkffmn0iyy8-gcc-12.3.0/include/c++/12.3.0/cstdio:42,
                 from /nix/store/h5kvfrjmpw792v8jg7nrzfkffmn0iyy8-gcc-12.3.0/include/c++/12.3.0/ext/string_conversions.h:43,
                 from /nix/store/h5kvfrjmpw792v8jg7nrzfkffmn0iyy8-gcc-12.3.0/include/c++/12.3.0/bits/basic_string.h:3968,
                 from /nix/store/h5kvfrjmpw792v8jg7nrzfkffmn0iyy8-gcc-12.3.0/include/c++/12.3.0/string:53,
                 from /nix/store/h5kvfrjmpw792v8jg7nrzfkffmn0iyy8-gcc-12.3.0/include/c++/12.3.0/bits/locale_classes.h:40,
                 from /nix/store/h5kvfrjmpw792v8jg7nrzfkffmn0iyy8-gcc-12.3.0/include/c++/12.3.0/bits/ios_base.h:41,
                 from /nix/store/h5kvfrjmpw792v8jg7nrzfkffmn0iyy8-gcc-12.3.0/include/c++/12.3.0/ios:42,
                 from /nix/store/h5kvfrjmpw792v8jg7nrzfkffmn0iyy8-gcc-12.3.0/include/c++/12.3.0/ostream:38,
                 from iostream:39:
/nix/store/y8wfrgk7br5rfz4221lfb9v8w3n0cnyd-glibc-2.37-8-dev/include/stdio.h:605:14: note: declared here
  605 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
/nix/store/74y3751gsixaz9797ib0hp7c658sp1y5-binutils-2.40/bin/ld: /tmp/ccOjvCBT.o: in function `main':
foo.cc:(.text.startup+0xc): warning: the `gets' function is dangerous and should not be used.

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