answer.code: In function ‘int main()’:
answer.code:41:15: error: no match for ‘operator>=’ (operand types are ‘std::string’ {aka ‘std::__cxx11::basic_string<char>’} and ‘std::__cxx11::basic_string<char>::size_type’ {aka ‘long unsigned int’})
   41 |         if(now>=a.size()) continue;
      |            ~~~^~~~~~~~~~
      |            |          |
      |            |          std::__cxx11::basic_string<char>::size_type {aka long unsigned int}
      |            std::string {aka std::__cxx11::basic_string<char>}
In file included from /usr/include/c++/11/regex:63,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:110,
                 from answer.code:2:
/usr/include/c++/11/bits/regex.h:1121:5: note: candidate: ‘template<class _BiIter> bool std::__cxx11::operator>=(const std::__cxx11::sub_match<_BiIter>&, const std::__cxx11::sub_match<_BiIter>&)’
 1121 |     operator>=(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/11/bits/regex.h:1121:5: note:   template argument deduction/substitution failed:
answer.code:41:24: note:   ‘std::string’ {aka ‘std::__cxx11::basic_string<char>’} is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
   41 |         if(now>=a.size()) continue;
      |                        ^
In file included from /usr/include/c++/11/regex:63,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:110,
                 from answer.code:2:
/usr/include/c++/11/bits/regex.h:1204:5: note: candidate: ‘template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator>=(std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&, const std::__cxx11::sub_match<_BiIter>&)’
 1204 |     operator>=(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/11/bits/regex.h:1204:5: note:   template argument deduction/substitution failed:
answer.code:41:24: note:   mismatched types ‘const std::__cxx11::sub_match<_BiIter>’ and ‘std::__cxx11::basic_string<char>::size_type’ {aka ‘long unsigned int’}
   41 |         if(now>=a.size()) continue;
      |                        ^
In file included from /usr/include/c++/11/regex:63,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:110,
                 from answer.code:2:
/usr/include/c++/11/bits/regex.h:1297:5: note: candidate: ‘template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator>=(const std::__cxx11::sub_match<_BiIter>&, std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&)’
 1297 |     operator>=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/11/bits/regex.h:1297:5: note:   template argument deduction/substitution failed:
answer.code:41:24: note:   ‘std::string’ {aka ‘std::__cxx11::basic_string<char>’} is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
   41 |         if(now>=a.size()) continue;
      |                        ^
In file included from /usr/include/c++/11/regex:63,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:110,
                 from answer.code:2:
/usr/include/c++/11/bits/regex.h:1371:5: note: candidate: ‘template<class _Bi_iter> bool std::__cxx11::operator>=(const typename std::iterator_traits<_Iter>::value_type*, const std::__cxx11::sub_match<_BiIter>&)’
 1371 |     operator>=(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/11/bits/regex.h:1371:5: note:   template argument deduction/substitution failed:
answer.code:41:24: note:   mismatched types ‘const std::__cxx11::sub_match<_BiIter>’ and ‘std::__cxx11::basic_string<char>::size_type’ {aka ‘long unsigned int’}
   41 |         if(now>=a.size()) continue;
      |                        ^
In file included from /usr/include/c++/11/regex:63,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:110,
                 from answer.code:2:
/usr/include/c++/11/bits/regex.h:1465:5: note: candidate: ‘template<class _Bi_iter> bool std::__cxx11::operator>=(const std::__cxx11::sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)’
 1465 |     operator>=(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/11/bits/regex.h:1465:5: note:   template argument deduction/substitution failed:
answer.code:41:24: note:   ‘std::string’ {aka ‘std::__cxx11::basic_string<char>’} is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
   41 |         if(now>=a.size()) continue;
      |                        ^
In file included from /usr/include/c++/11/regex:63,
                 from /usr/include/x86_64-linux-gnu/c++/11/bits/stdc++.h:110,
                 from answer.code:2:
/usr/include/c++/11/bits/regex.h:1542:5: note: candidate: ‘template<class _Bi_iter> bool std::__cxx11::operator>=(const typename std::iterator_traits<_Iter>::value_type&, const std::__cxx11::sub_match<_BiIter>&)’
 1542 |     operato...