Eroare de compilare: In file included from /usr/include/c++/6/bits/stl_algobase.h:71:0, 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 main.cpp:1: /usr/include/c++/6/bits/predefined_ops.h: In instantiation of 'constexpr bool __gnu_cxx::__ops::_Iter_less_iter::operator()(_Iterator1, _Iterator2) const [with _Iterator1 = pista*; _Iterator2 = pista*]': /usr/include/c++/6/bits/stl_algo.h:1844:14: required from 'void std::__insertion_sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = pista*; _Compare = __gnu_cxx::__ops::_Iter_less_iter]' /usr/include/c++/6/bits/stl_algo.h:1882:25: required from 'void std::__final_insertion_sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = pista*; _Compare = __gnu_cxx::__ops::_Iter_less_iter]' /usr/include/c++/6/bits/stl_algo.h:1968:31: required from 'void std::__sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = pista*; _Compare = __gnu_cxx::__ops::_Iter_less_iter]' /usr/include/c++/6/bits/stl_algo.h:4707:18: required from 'void std::sort(_RAIter, _RAIter) [with _RAIter = pista*]' main.cpp:93:26: required from here /usr/include/c++/6/bits/predefined_ops.h:43:23: error: no match for 'operator<' (operand types are 'pista' and 'pista') { return *__it1 < *__it2; } ~~~~~~~^~~~~~~~ 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 main.cpp:1: /usr/include/c++/6/bits/stl_iterator.h:885:5: note: candidate: template<class _IteratorL, class _IteratorR, class _Container> bool __gnu_cxx::operator<(const __gnu_cxx::__normal_iterator<_IteratorL, _Container>&, const __gnu_cxx::__normal_iterator<_IteratorR, _Container>&) operator<(const __normal_iterator<_IteratorL, _Container>& __lhs, ^~~~~~~~ /usr/include/c++/6/bits/stl_iterator.h:885:5: note: template argument deduction/substitution failed: In file included from /usr/include/c++/6/bits/stl_algobase.h:71:0, 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 main.cpp:1: /usr/include/c++/6/bits/predefined_ops.h:43:23: note: 'pista' is not derived from 'const __gnu_cxx::__normal_iterator<_IteratorL, _Container>' { return *__it1 < *__it2; } ~~~~~~~^~~~~~~~ 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 main.cpp:1: /usr/include/c++/6/bits/stl_iterator.h:892:5: note: candidate: template<class _Iterator, class _Container> bool __gnu_cxx::operator<(const __gnu_cxx::__normal_iterator<_Iterator, _Container>&, const __gnu_cxx::__normal_iterator<_Iterator, _Container>&) operator<(const __normal_iterator<_Iterator, _Container>& __lhs, ^~~~~~~~ /usr/include/c++/6/bits/stl_iterator.h:892:5: note: template argument deduction/substitution failed: In file included from /usr/include/c++/6/bits/stl_algobase.h:71:0, 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 main.cpp:1: Non zero exit status: 1