Eroare de compilare: main.cpp: In function 'int main()': main.cpp:32:5: error: reference to 'prev' is ambiguous prev=0; ^~~~ main.cpp:9:6: note: candidates are: bool prev bool prev=0; ^~~~ In file included from /usr/include/c++/6/bits/stl_algobase.h:66:0, from /usr/include/c++/6/bits/char_traits.h:39, from /usr/include/c++/6/ios:40, from /usr/include/c++/6/istream:38, from /usr/include/c++/6/sstream:38, from /usr/include/c++/6/complex:45, from /usr/include/c++/6/ccomplex:39, from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:52, from main.cpp:1: /usr/include/c++/6/bits/stl_iterator_base_funcs.h:217:5: note: template<class _BidirectionalIterator> _BidirectionalIterator std::prev(_BidirectionalIterator, typename std::iterator_traits<_Iter>::difference_type) prev(_BidirectionalIterator __x, typename ^~~~ main.cpp:37:8: error: reference to 'prev' is ambiguous if(prev==0) ^~~~ main.cpp:9:6: note: candidates are: bool prev bool prev=0; ^~~~ In file included from /usr/include/c++/6/bits/stl_algobase.h:66:0, from /usr/include/c++/6/bits/char_traits.h:39, from /usr/include/c++/6/ios:40, from /usr/include/c++/6/istream:38, from /usr/include/c++/6/sstream:38, from /usr/include/c++/6/complex:45, from /usr/include/c++/6/ccomplex:39, from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:52, from main.cpp:1: /usr/include/c++/6/bits/stl_iterator_base_funcs.h:217:5: note: template<class _BidirectionalIterator> _BidirectionalIterator std::prev(_BidirectionalIterator, typename std::iterator_traits<_Iter>::difference_type) prev(_BidirectionalIterator __x, typename ^~~~ main.cpp:50:5: error: reference to 'prev' is ambiguous prev=1; ^~~~ main.cpp:9:6: note: candidates are: bool prev bool prev=0; ^~~~ In file included from /usr/include/c++/6/bits/stl_algobase.h:66:0, from /usr/include/c++/6/bits/char_traits.h:39, from /usr/include/c++/6/ios:40, from /usr/include/c++/6/istream:38, from /usr/include/c++/6/sstream:38, from /usr/include/c++/6/complex:45, from /usr/include/c++/6/ccomplex:39, Non zero exit status: 1