/in/foo.cc: In function 'void bfs(int)':
/in/foo.cc:25:10: error: 'N' was not declared in this scope
  if(t == N)
          ^
/in/foo.cc:28:3: error: break statement not within loop or switch
   break;
   ^~~~~
/in/foo.cc:30:21: error: 'N' was not declared in this scope
  for(int i = 0; i < N; i++)
                     ^
/in/foo.cc:35:4: error: 'p' was not declared in this scope
    p[t] = n[i];
    ^
/in/foo.cc:36:9: error: no match for 'operator+' (operand types are 'std::vector<char>' and 'int')
    bfs(n+1);
        ~^~
In file included from /usr/include/c++/6/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/6/bits/char_traits.h:39,
                 from /usr/include/c++/6/ios:40,
                 from /usr/include/c++/6/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:1:
/usr/include/c++/6/bits/stl_iterator.h:341:5: note: candidate: template<class _Iterator> std::reverse_iterator<_Iterator> std::operator+(typename std::reverse_iterator<_Iterator>::difference_type, const std::reverse_iterator<_Iterator>&)
     operator+(typename reverse_iterator<_Iterator>::difference_type __n,
     ^~~~~~~~
/usr/include/c++/6/bits/stl_iterator.h:341:5: note:   template argument deduction/substitution failed:
/in/foo.cc:36:10: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and 'int'
    bfs(n+1);
          ^
In file included from /usr/include/c++/6/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/6/bits/char_traits.h:39,
                 from /usr/include/c++/6/ios:40,
                 from /usr/include/c++/6/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:1:
/usr/include/c++/6/bits/stl_iterator.h:1200:5: note: candidate: template<class _Iterator> std::move_iterator<_IteratorL> std::operator+(typename std::move_iterator<_IteratorL>::difference_type, const std::move_iterator<_IteratorL>&)
     operator+(typename move_iterator<_Iterator>::difference_type __n,
     ^~~~~~~~
/usr/include/c++/6/bits/stl_iterator.h:1200:5: note:   template argument deduction/substitution failed:
/in/foo.cc:36:10: note:   mismatched types 'const std::move_iterator<_IteratorL>' and 'int'
    bfs(n+1);
          ^
In file included from /usr/include/c++/6/string:52:0,
                 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/c++/6/bits/basic_string.h:4944:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Alloc> std::operator+(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)
     operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
     ^~~~~~~~
/usr/include/c++/6/bits/basic_string.h:4944:5: note:   template argument deduction/substitution failed:
/in/foo.cc:36:10: note:   'std::vector<char>' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>'
    bfs(n+1);
          ^
In file included from /usr/include/c++/6/string:53:0,
                 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/c++/6/bits/basic_string.tcc:1147:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Alloc> std::operator+(const _CharT*, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)
     operator+(const _CharT* __lhs,
     ^~~~~~~~
/usr/include/c++/6/bits/basic_string.tcc:1147:5: note:   template argument deduction/substitution failed:
/in/foo.cc:36:10: note:   mismatched types 'const _CharT*' and 'std::vector<char>'
    bfs(n+1);
          ^
In file included from /usr/include/c++/6/string:53:0,
                 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/c++/6/bits/basic_string.tcc:1163:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Alloc> std::operator+(_CharT, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)
     operator+(_CharT __lhs, const basic_string<_CharT, _Traits, _Alloc>& __rhs)
     ^~~~~~~~
/usr/include/c++/6/bits/basic_string.tcc:1163:5: note:   template argument deduction/substitution failed:
/in/foo.cc:36:10: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>' and 'int'
    bfs(n+1);
          ^
In file included from /usr/include/c++/6/string:52:0,
                 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/c++/6/bits/basic_string.h:4981:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Alloc> std::operator+(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const _CharT*)
     operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
     ^~~~~~~~
/usr/include/c++/6/bits/basic_string.h:4981:5: note:   template argument deduction/substitution failed:
/in/foo.cc:36:10: note:   'std::vector<char>' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>'
    bfs(n+1);
          ^
In file included from /usr/include/c++/6/string:52:0,
                 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/c++/6/bits/basic_string.h:4997:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Alloc> std::operator+(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, _CharT)
     operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs, _CharT __rhs)
     ^~~~~~~~
/usr/include/c++/6/bits/basic_string.h:4997:5: note:   template argument deduction/substitution failed:
/in/foo.cc:36:10: note:   'std::vector<char>' is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>'
    bfs(n+1);
          ^
In file included from /usr/include/c++/6/string:52:0,
                 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/c++/6/bits/basic_string.h:5009:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> std::__cxx11::basic_string<_CharT, _Traits, _Alloc> std::operator+(std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&&, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)
     operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
     ^~~~~~~~
/usr/include/c++/6/bits/basic_string.h:5009:5: note:   template argument deduction/substitution failed:
/in/foo.cc:36:10: note:   'std::vector<char>' is not derived from 'std::__cxx11::basic_string<_CharT, _Traits, _Alloc>'
    bfs(n+1);
          ^
In file included from /usr/include/c++/6/string:52:0,
                 from /usr/include/c++/6/bits/loca