foo.cc: In function 'int main()':
foo.cc:13:9: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
   13 |     gets(s);
      |     ~~~~^~~
In file included from /nix/store/jgdz5wfqc6q6qhy17lsqnfpbkfi1fcar-gcc-12.2.0/include/c++/12.2.0/cstdio:42,
                 from /nix/store/jgdz5wfqc6q6qhy17lsqnfpbkfi1fcar-gcc-12.2.0/include/c++/12.2.0/ext/string_conversions.h:43,
                 from /nix/store/jgdz5wfqc6q6qhy17lsqnfpbkfi1fcar-gcc-12.2.0/include/c++/12.2.0/bits/basic_string.h:3960,
                 from /nix/store/jgdz5wfqc6q6qhy17lsqnfpbkfi1fcar-gcc-12.2.0/include/c++/12.2.0/string:53,
                 from /nix/store/jgdz5wfqc6q6qhy17lsqnfpbkfi1fcar-gcc-12.2.0/include/c++/12.2.0/bits/locale_classes.h:40,
                 from /nix/store/jgdz5wfqc6q6qhy17lsqnfpbkfi1fcar-gcc-12.2.0/include/c++/12.2.0/bits/ios_base.h:41,
                 from /nix/store/jgdz5wfqc6q6qhy17lsqnfpbkfi1fcar-gcc-12.2.0/include/c++/12.2.0/ios:42,
                 from /nix/store/jgdz5wfqc6q6qhy17lsqnfpbkfi1fcar-gcc-12.2.0/include/c++/12.2.0/ostream:38,
                 from iostream:39:
/nix/store/linb70pgp53f0kygxm5wk163dx22d681-glibc-2.37-45-dev/include/stdio.h:605:14: note: declared here
  605 | extern char *gets (char *__s) __wur __attribute_deprecated__;
      |              ^~~~
foo.cc:17:17: error: 'strlen' was not declared in this scope
   17 |     while(flag2<strlen(s))
      |                 ^~~~~~
foo.cc:2:1: note: 'strlen' is defined in header '<cstring>'; did you forget to '#include <cstring>'?
    1 | #include<iostream>
  +++ |+#include <cstring>
    2 | using namespace std;

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