Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:75:12: error: reference to ‘prev’ is ambiguous memset(prev, -1 , (n+1)* sizeof(int) ); ^ user.cpp:19:5: note: candidates are: int prev [100100] int prev[N]; ^ In file included from /usr/include/c++/4.8/bits/stl_algobase.h:66:0, from /usr/include/c++/4.8/bits/char_traits.h:39, from /usr/include/c++/4.8/ios:40, from /usr/include/c++/4.8/ostream:38, from /usr/include/c++/4.8/iostream:39, from user.cpp:1: /usr/include/c++/4.8/bits/stl_iterator_base_funcs.h:193:5: note: template<class _BidirectionalIterator> _BidirectionalIterator std::prev(_BidirectionalIterator, typename std::iterator_traits<_Iter>::difference_type) prev(_BidirectionalIterator __x, typename ^ user.cpp:79:17: error: reference to ‘prev’ is ambiguous if( prev[ el[i].x ] == -1 ){ ^ user.cpp:19:5: note: candidates are: int prev [100100] int prev[N]; ^ In file included from /usr/include/c++/4.8/bits/stl_algobase.h:66:0, from /usr/include/c++/4.8/bits/char_traits.h:39, from /usr/include/c++/4.8/ios:40, from /usr/include/c++/4.8/ostream:38, from /usr/include/c++/4.8/iostream:39, from user.cpp:1: /usr/include/c++/4.8/bits/stl_iterator_base_funcs.h:193:5: note: template<class _BidirectionalIterator> _BidirectionalIterator std::prev(_BidirectionalIterator, typename std::iterator_traits<_Iter>::difference_type) prev(_BidirectionalIterator __x, typename ^ user.cpp:80:17: error: reference to ‘prev’ is ambiguous prev [ el[i].x ] = el[i].y ; ^ user.cpp:19:5: note: candidates are: int prev [100100] int prev[N]; ^ In file included from /usr/include/c++/4.8/bits/stl_algobase.h:66:0, from /usr/include/c++/4.8/bits/char_traits.h:39, from /usr/include/c++/4.8/ios:40, from /usr/include/c++/4.8/ostream:38, from /usr/include/c++/4.8/iostream:39, from user.cpp:1: /usr/include/c++/4.8/bits/stl_iterator_base_funcs.h:193:5: note: template<class _BidirectionalIterator> _BidirectionalIterator std::prev(_BidirectionalIterator, typename std::iterator_traits<_Iter>::difference_type) prev(_BidirectionalIterator __x, typename ^ user.cpp:83:26: error: reference to ‘prev’ is ambiguous update ( prev[ el[i].x ] , - el[i].x ); ^ user.cpp:19:5: note: candidates are: int prev [100100]