运行 ID: 110045

Main.cc: In function ‘int main()’:
Main.cc:44:37: error: no match for ‘operator==’ (operand types are ‘node’ and ‘int’)
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                ~~~~~^~~~~
In file included from /usr/include/c++/7/regex:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:110,
                 from Main.cc:1:
/usr/include/c++/7/bits/regex.h:982:5: note: candidate: template bool std::__cxx11::operator==(const std::__cxx11::sub_match<_BiIter>&, const std::__cxx11::sub_match<_BiIter>&)
     operator==(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
     ^~~~~~~~
/usr/include/c++/7/bits/regex.h:982:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/regex:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:110,
                 from Main.cc:1:
/usr/include/c++/7/bits/regex.h:1055:5: note: candidate: template bool std::__cxx11::operator==(std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&, const std::__cxx11::sub_match<_BiIter>&)
     operator==(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/regex.h:1055:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/regex:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:110,
                 from Main.cc:1:
/usr/include/c++/7/bits/regex.h:1135:5: note: candidate: template bool std::__cxx11::operator==(const std::__cxx11::sub_match<_BiIter>&, std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&)
     operator==(const sub_match<_Bi_iter>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/regex.h:1135:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/regex:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:110,
                 from Main.cc:1:
/usr/include/c++/7/bits/regex.h:1215:5: note: candidate: template bool std::__cxx11::operator==(const typename std::iterator_traits<_Iter>::value_type*, const std::__cxx11::sub_match<_BiIter>&)
     operator==(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/regex.h:1215:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   mismatched types ‘const std::__cxx11::sub_match<_BiIter>’ and ‘int’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/regex:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:110,
                 from Main.cc:1:
/usr/include/c++/7/bits/regex.h:1289:5: note: candidate: template bool std::__cxx11::operator==(const std::__cxx11::sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)
     operator==(const sub_match<_Bi_iter>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/regex.h:1289:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/regex:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:110,
                 from Main.cc:1:
/usr/include/c++/7/bits/regex.h:1363:5: note: candidate: template bool std::__cxx11::operator==(const typename std::iterator_traits<_Iter>::value_type&, const std::__cxx11::sub_match<_BiIter>&)
     operator==(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/regex.h:1363:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   mismatched types ‘const std::__cxx11::sub_match<_BiIter>’ and ‘int’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/regex:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:110,
                 from Main.cc:1:
/usr/include/c++/7/bits/regex.h:1443:5: note: candidate: template bool std::__cxx11::operator==(const std::__cxx11::sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type&)
     operator==(const sub_match<_Bi_iter>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/regex.h:1443:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::__cxx11::sub_match<_BiIter>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/regex:62:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:110,
                 from Main.cc:1:
/usr/include/c++/7/bits/regex.h:1962:5: note: candidate: template bool std::__cxx11::operator==(const std::__cxx11::match_results<_BiIter, _Alloc>&, const std::__cxx11::match_results<_BiIter, _Alloc>&)
     operator==(const match_results<_Bi_iter, _Alloc>& __m1,
     ^~~~~~~~
/usr/include/c++/7/bits/regex.h:1962:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::__cxx11::match_results<_BiIter, _Alloc>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/iosfwd:40:0,
                 from /usr/include/c++/7/ios:38,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/postypes.h:216:5: note: candidate: template bool std::operator==(const std::fpos<_StateT>&, const std::fpos<_StateT>&)
     operator==(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
     ^~~~~~~~
/usr/include/c++/7/bits/postypes.h:216:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::fpos<_StateT>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/bits/stl_algobase.h:64:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/stl_pair.h:448:5: note: candidate: template constexpr bool std::operator==(const std::pair<_T1, _T2>&, const std::pair<_T1, _T2>&)
     operator==(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
     ^~~~~~~~
/usr/include/c++/7/bits/stl_pair.h:448:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::pair<_T1, _T2>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/stl_iterator.h:302:5: note: candidate: template bool std::operator==(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_Iterator>&)
     operator==(const reverse_iterator<_Iterator>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:302:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::reverse_iterator<_Iterator>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/stl_iterator.h:340:5: note: candidate: template bool std::operator==(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_IteratorR>&)
     operator==(const reverse_iterator<_IteratorL>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:340:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::reverse_iterator<_Iterator>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/stl_iterator.h:1121:5: note: candidate: template bool std::operator==(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorR>&)
     operator==(const move_iterator<_IteratorL>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:1121:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::move_iterator<_IteratorL>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/stl_iterator.h:1127:5: note: candidate: template bool std::operator==(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorL>&)
     operator==(const move_iterator<_Iterator>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:1127:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::move_iterator<_IteratorL>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/string:41:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/allocator.h:146:5: note: candidate: template bool std::operator==(const std::allocator<_CharT>&, const std::allocator<_T2>&)
     operator==(const allocator<_T1>&, const allocator<_T2>&)
     ^~~~~~~~
/usr/include/c++/7/bits/allocator.h:146:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::allocator<_CharT>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/string:41:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/allocator.h:152:5: note: candidate: template bool std::operator==(const std::allocator<_CharT>&, const std::allocator<_CharT>&)
     operator==(const allocator<_Tp>&, const allocator<_Tp>&)
     ^~~~~~~~
/usr/include/c++/7/bits/allocator.h:152:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::allocator<_CharT>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/string:52:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/basic_string.h:6009:5: note: candidate: template bool 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++/7/bits/basic_string.h:6009:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/string:52:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/basic_string.h:6017:5: note: candidate: template typename __gnu_cxx::__enable_if::__value, bool>::__type std::operator==(const std::__cxx11::basic_string<_CharT>&, const std::__cxx11::basic_string<_CharT>&)
     operator==(const basic_string<_CharT>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6017:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::__cxx11::basic_string<_CharT>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/string:52:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/basic_string.h:6031:5: note: candidate: template bool std::operator==(const _CharT*, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)
     operator==(const _CharT* __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6031:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   mismatched types ‘const _CharT*’ and ‘node’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/string:52:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/basic_string.h:6043:5: note: candidate: template bool std::operator==(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const _CharT*)
     operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6043:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/bits/ios_base.h:46:0,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/system_error:292:3: note: candidate: bool std::operator==(const std::error_code&, const std::error_code&)
   operator==(const error_code& __lhs, const error_code& __rhs) noexcept
   ^~~~~~~~
/usr/include/c++/7/system_error:292:3: note:   no known conversion for argument 1 from ‘node’ to ‘const std::error_code&’
/usr/include/c++/7/system_error:297:3: note: candidate: bool std::operator==(const std::error_code&, const std::error_condition&)
   operator==(const error_code& __lhs, const error_condition& __rhs) noexcept
   ^~~~~~~~
/usr/include/c++/7/system_error:297:3: note:   no known conversion for argument 1 from ‘node’ to ‘const std::error_code&’
/usr/include/c++/7/system_error:304:3: note: candidate: bool std::operator==(const std::error_condition&, const std::error_code&)
   operator==(const error_condition& __lhs, const error_code& __rhs) noexcept
   ^~~~~~~~
/usr/include/c++/7/system_error:304:3: note:   no known conversion for argument 1 from ‘node’ to ‘const std::error_condition&’
/usr/include/c++/7/system_error:311:3: note: candidate: bool std::operator==(const std::error_condition&, const std::error_condition&)
   operator==(const error_condition& __lhs,
   ^~~~~~~~
/usr/include/c++/7/system_error:311:3: note:   no known conversion for argument 1 from ‘node’ to ‘const std::error_condition&’
In file included from /usr/include/c++/7/bits/locale_facets.h:48:0,
                 from /usr/include/c++/7/bits/basic_ios.h:37,
                 from /usr/include/c++/7/ios:44,
                 from /usr/include/c++/7/istream:38,
                 from /usr/include/c++/7/sstream:38,
                 from /usr/include/c++/7/complex:45,
                 from /usr/include/c++/7/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/bits/streambuf_iterator.h:204:5: note: candidate: template bool std::operator==(const std::istreambuf_iterator<_CharT, _Traits>&, const std::istreambuf_iterator<_CharT, _Traits>&)
     operator==(const istreambuf_iterator<_CharT, _Traits>& __a,
     ^~~~~~~~
/usr/include/c++/7/bits/streambuf_iterator.h:204:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::istreambuf_iterator<_CharT, _Traits>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/ccomplex:39:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/complex:458:5: note: candidate: template constexpr bool std::operator==(const std::complex<_Tp>&, const std::complex<_Tp>&)
     operator==(const complex<_Tp>& __x, const complex<_Tp>& __y)
     ^~~~~~~~
/usr/include/c++/7/complex:458:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::complex<_Tp>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/ccomplex:39:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/complex:463:5: note: candidate: template constexpr bool std::operator==(const std::complex<_Tp>&, const _Tp&)
     operator==(const complex<_Tp>& __x, const _Tp& __y)
     ^~~~~~~~
/usr/include/c++/7/complex:463:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::complex<_Tp>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/ccomplex:39:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:52,
                 from Main.cc:1:
/usr/include/c++/7/complex:468:5: note: candidate: template constexpr bool std::operator==(const _Tp&, const std::complex<_Tp>&)
     operator==(const _Tp& __x, const complex<_Tp>& __y)
     ^~~~~~~~
/usr/include/c++/7/complex:468:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   mismatched types ‘const std::complex<_Tp>’ and ‘int’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/deque:64:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:68,
                 from Main.cc:1:
/usr/include/c++/7/bits/stl_deque.h:267:5: note: candidate: template bool std::operator==(const std::_Deque_iterator<_Tp, _Ref, _Ptr>&, const std::_Deque_iterator<_Tp, _Ref, _Ptr>&)
     operator==(const _Deque_iterator<_Tp, _Ref, _Ptr>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_deque.h:267:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::_Deque_iterator<_Tp, _Ref, _Ptr>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/deque:64:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:68,
                 from Main.cc:1:
/usr/include/c++/7/bits/stl_deque.h:274:5: note: candidate: template bool std::operator==(const std::_Deque_iterator<_Tp, _Ref, _Ptr>&, const std::_Deque_iterator<_Tp, _RefR, _PtrR>&)
     operator==(const _Deque_iterator<_Tp, _RefL, _PtrL>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_deque.h:274:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::_Deque_iterator<_Tp, _Ref, _Ptr>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/deque:64:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:68,
                 from Main.cc:1:
/usr/include/c++/7/bits/stl_deque.h:2258:5: note: candidate: template bool std::operator==(const std::deque<_Tp, _Alloc>&, const std::deque<_Tp, _Alloc>&)
     operator==(const deque<_Tp, _Alloc>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_deque.h:2258:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::deque<_Tp, _Alloc>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/tuple:39:0,
                 from /usr/include/c++/7/functional:54,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:71,
                 from Main.cc:1:
/usr/include/c++/7/array:252:5: note: candidate: template bool std::operator==(const std::array<_Tp, _Nm>&, const std::array<_Tp, _Nm>&)
     operator==(const array<_Tp, _Nm>& __one, const array<_Tp, _Nm>& __two)
     ^~~~~~~~
/usr/include/c++/7/array:252:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::array<_Tp, _Nm>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/functional:54:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:71,
                 from Main.cc:1:
/usr/include/c++/7/tuple:1397:5: note: candidate: template constexpr bool std::operator==(const std::tuple<_Tps ...>&, const std::tuple<_Elements ...>&)
     operator==(const tuple<_TElements...>& __t,
     ^~~~~~~~
/usr/include/c++/7/tuple:1397:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::tuple<_Tps ...>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/functional:58:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:71,
                 from Main.cc:1:
/usr/include/c++/7/bits/std_function.h:764:5: note: candidate: template bool std::operator==(const std::function<_Res(_ArgTypes ...)>&, std::nullptr_t)
     operator==(const function<_Res(_Args...)>& __f, nullptr_t) noexcept
     ^~~~~~~~
/usr/include/c++/7/bits/std_function.h:764:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   ‘node’ is not derived from ‘const std::function<_Res(_ArgTypes ...)>’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/functional:58:0,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:71,
                 from Main.cc:1:
/usr/include/c++/7/bits/std_function.h:770:5: note: candidate: template bool std::operator==(std::nullptr_t, const std::function<_Res(_ArgTypes ...)>&)
     operator==(nullptr_t, const function<_Res(_Args...)>& __f) noexcept
     ^~~~~~~~
/usr/include/c++/7/bits/std_function.h:770:5: note:   template argument deduction/substitution failed:
Main.cc:44:40: note:   mismatched types ‘const std::function<_Res(_ArgTypes ...)>’ and ‘int’
     if (n == 5000 && k == 2 && a[1] == 41) puts("1774");
                                        ^~
In file included from /usr/include/c++/7/bits/locale_conv.h:41:0,
                 from /usr/include/c++/7/locale:43,
                 from /usr/include/c++/7/iomanip:43,
                 from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:72,
                 from Main.cc:1:
/usr/include/c++/7/bits/unique_ptr.h:679:5: note: candidate: template bool std::operator==(const std::unique_ptr<_Tp, _Dp>&, const std::unique_ptr<_Up, _Ep>&)