foo.cpp: In function 'void de(int)':
foo.cpp:45:5: error: reference to 'next' is ambiguous
     next[next[i].l].r=next[i].r;
     ^
foo.cpp:42:2: note: candidates are: New next [50010]
 }next[50010];
  ^
In file included from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/stl_algobase.h:66:0,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/char_traits.h:39,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/ios:40,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/ostream:38,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/iostream:39,
                 from foo.cpp:1:
C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/stl_iterator_base_funcs.h:184:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^
foo.cpp:45:10: error: reference to 'next' is ambiguous
     next[next[i].l].r=next[i].r;
          ^
foo.cpp:42:2: note: candidates are: New next [50010]
 }next[50010];
  ^
In file included from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/stl_algobase.h:66:0,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/char_traits.h:39,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/ios:40,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/ostream:38,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/iostream:39,
                 from foo.cpp:1:
C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/stl_iterator_base_funcs.h:184:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^
foo.cpp:45:23: error: reference to 'next' is ambiguous
     next[next[i].l].r=next[i].r;
                       ^
foo.cpp:42:2: note: candidates are: New next [50010]
 }next[50010];
  ^
In file included from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/stl_algobase.h:66:0,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/char_traits.h:39,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/ios:40,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/ostream:38,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/iostream:39,
                 from foo.cpp:1:
C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/stl_iterator_base_funcs.h:184:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^
foo.cpp:46:5: error: reference to 'next' is ambiguous
     next[next[i].r].l=next[i].l;
     ^
foo.cpp:42:2: note: candidates are: New next [50010]
 }next[50010];
  ^
In file included from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/stl_algobase.h:66:0,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/char_traits.h:39,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/ios:40,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/ostream:38,
                 from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/iostream:39,
                 from foo.cpp:1:
C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/stl_iterator_base_funcs.h:184:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^
foo.cpp:46:10: error: reference to 'next' is ambiguous
     next[next[i].r].l=next[i].l;
          ^
foo.cpp:42:2: note: candidates are: New next [50010]
 }next[50010];
  ^
In file included from C:/TDM-GCC-32/lib/gcc/mingw32/4.9.2/include/c++/bits/stl_algobase.h:66:0,