In file included from /usr/include/c++/13/set:64,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/stdc++.h:158,
                 from answer.code:1:
/usr/include/c++/13/bits/stl_multiset.h: In instantiation of ‘void std::multiset<_Key, _Compare, _Alloc>::insert(_InputIterator, _InputIterator) [with _InputIterator = double; _Key = Line; _Compare = std::less<Line>; _Alloc = std::allocator<Line>]’:
answer.code:66:13:   required from here
/usr/include/c++/13/bits/stl_multiset.h:554:37: error: no matching function for call to ‘std::_Rb_tree<Line, Line, std::_Identity<Line>, std::less<Line>, std::allocator<Line> >::_M_insert_range_equal(double&, double&)’
  554 |         { _M_t._M_insert_range_equal(__first, __last); }
      |           ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/13/map:62,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/stdc++.h:152:
/usr/include/c++/13/bits/stl_tree.h:1117:9: note: candidate: ‘template<class _InputIterator> std::__enable_if_t<std::is_same<_Val, typename std::iterator_traits<_InputIterator>::value_type>::value> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::_M_insert_range_equal(_InputIterator, _InputIterator) [with _Key = Line; _Val = Line; _KeyOfValue = std::_Identity<Line>; _Compare = std::less<Line>; _Alloc = std::allocator<Line>]’
 1117 |         _M_insert_range_equal(_InputIterator __first, _InputIterator __last)
      |         ^~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/13/bits/stl_tree.h:1117:9: note:   template argument deduction/substitution failed:
/usr/include/c++/13/bits/stl_tree.h: In substitution of ‘template<class _InputIterator> std::__enable_if_t<std::is_same<Line, typename std::iterator_traits< <template-parameter-1-1> >::value_type>::value, void> std::_Rb_tree<Line, Line, std::_Identity<Line>, std::less<Line>, std::allocator<Line> >::_M_insert_range_equal(_InputIterator, _InputIterator) [with _InputIterator = double]’:
/usr/include/c++/13/bits/stl_multiset.h:554:30:   required from ‘void std::multiset<_Key, _Compare, _Alloc>::insert(_InputIterator, _InputIterator) [with _InputIterator = double; _Key = Line; _Compare = std::less<Line>; _Alloc = std::allocator<Line>]’
answer.code:66:13:   required from here
/usr/include/c++/13/bits/stl_tree.h:1117:9: error: no type named ‘value_type’ in ‘struct std::iterator_traits<double>’
/usr/include/c++/13/bits/stl_multiset.h: In instantiation of ‘void std::multiset<_Key, _Compare, _Alloc>::insert(_InputIterator, _InputIterator) [with _InputIterator = double; _Key = Line; _Compare = std::less<Line>; _Alloc = std::allocator<Line>]’:
answer.code:66:13:   required from here
/usr/include/c++/13/bits/stl_tree.h:1126:9: note: candidate: ‘template<class _InputIterator> std::__enable_if_t<(! std::is_same<_Val, typename std::iterator_traits<_InputIterator>::value_type>::value)> std::_Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::_M_insert_range_equal(_InputIterator, _InputIterator) [with _Key = Line; _Val = Line; _KeyOfValue = std::_Identity<Line>; _Compare = std::less<Line>; _Alloc = std::allocator<Line>]’
 1126 |         _M_insert_range_equal(_InputIterator __first, _InputIterator __last)
      |         ^~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/13/bits/stl_tree.h:1126:9: note:   template argument deduction/substitution failed:
/usr/include/c++/13/bits/stl_tree.h: In substitution of ‘template<class _InputIterator> std::__enable_if_t<(! std::is_same<Line, typename std::iterator_traits< <template-parameter-1-1> >::value_type>::value), void> std::_Rb_tree<Line, Line, std::_Identity<Line>, std::less<Line>, std::allocator<Line> >::_M_insert_range_equal(_InputIterator, _InputIterator) [with _InputIterator = double]’:
/usr/include/c++/13/bits/stl_multiset.h:554:30:   required from ‘void std::multiset<_Key, _Compare, _Alloc>::insert(_InputIterator, _InputIterator) [with _InputIterator = double; _Key = Line; _Compare = std::less<Line>; _Alloc = std::allocator<Line>]’
answer.code:66:13:   required from here
/usr/include/c++/13/bits/stl_tree.h:1108:59: error: no type named ‘value_type’ in ‘struct std::iterator_traits<double>’
 1108 |         __enable_if_t<!__same_value_type<_InputIterator>::value>
      |                                                           ^~~~~