/in/foo.cc: In function 'int dfs(int, int, int, int, int)':
/in/foo.cc:53:18: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
      if(tag=-1||v)
                  ^
/in/foo.cc:84:5: error: reference to 'next' is ambiguous
     next[sx1][sy1][mx1][my1][0]=sx1+dx[i];
     ^~~~
/in/foo.cc:14:63: note: candidates are: int next [30][30][30][30][4]
 int n,m,data[50][50][5],dis[30][30][30][30],sx,sy,ex,ey,mx,my,next[30][30][30][30][4],ans;  
                                                               ^~~~
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/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:2:
/usr/include/c++/6/bits/stl_iterator_base_funcs.h:205:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
/in/foo.cc:85:5: error: reference to 'next' is ambiguous
     next[sx1][sy1][mx1][my1][1]=sy1+dy[i];
     ^~~~
/in/foo.cc:14:63: note: candidates are: int next [30][30][30][30][4]
 int n,m,data[50][50][5],dis[30][30][30][30],sx,sy,ex,ey,mx,my,next[30][30][30][30][4],ans;  
                                                               ^~~~
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/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:2:
/usr/include/c++/6/bits/stl_iterator_base_funcs.h:205:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
/in/foo.cc:86:5: error: reference to 'next' is ambiguous
     next[sx1][sy1][mx1][my1][2]=mx2;
     ^~~~
/in/foo.cc:14:63: note: candidates are: int next [30][30][30][30][4]
 int n,m,data[50][50][5],dis[30][30][30][30],sx,sy,ex,ey,mx,my,next[30][30][30][30][4],ans;  
                                                               ^~~~
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/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:2:
/usr/include/c++/6/bits/stl_iterator_base_funcs.h:205:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
/in/foo.cc:87:5: error: reference to 'next' is ambiguous
     next[sx1][sy1][mx1][my1][3]=my2;
     ^~~~
/in/foo.cc:14:63: note: candidates are: int next [30][30][30][30][4]
 int n,m,data[50][50][5],dis[30][30][30][30],sx,sy,ex,ey,mx,my,next[30][30][30][30][4],ans;  
                                                               ^~~~
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/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:2:
/usr/include/c++/6/bits/stl_iterator_base_funcs.h:205:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:149:6: error: reference to 'next' is ambiguous
   if(next[x][y][xx][yy][0]>x)
      ^~~~
/in/foo.cc:14:63: note: candidates are: int next [30][30][30][30][4]
 int n,m,data[50][50][5],dis[30][30][30][30],sx,sy,ex,ey,mx,my,next[30][30][30][30][4],ans;  
                                                               ^~~~
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/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:2:
/usr/include/c++/6/bits/stl_iterator_base_funcs.h:205:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
/in/foo.cc:151:6: error: reference to 'next' is ambiguous
   if(next[x][y][xx][yy][0]<x)
      ^~~~
/in/foo.cc:14:63: note: candidates are: int next [30][30][30][30][4]
 int n,m,data[50][50][5],dis[30][30][30][30],sx,sy,ex,ey,mx,my,next[30][30][30][30][4],ans;  
                                                               ^~~~
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/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:2:
/usr/include/c++/6/bits/stl_iterator_base_funcs.h:205:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
/in/foo.cc:153:6: error: reference to 'next' is ambiguous
   if(next[x][y][xx][yy][1]>y)
      ^~~~
/in/foo.cc:14:63: note: candidates are: int next [30][30][30][30][4]
 int n,m,data[50][50][5],dis[30][30][30][30],sx,sy,ex,ey,mx,my,next[30][30][30][30][4],ans;  
                                                               ^~~~
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/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:2:
/usr/include/c++/6/bits/stl_iterator_base_funcs.h:205:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
/in/foo.cc:155:6: error: reference to 'next' is ambiguous
   if(next[x][y][xx][yy][1]<y)
      ^~~~
/in/foo.cc:14:63: note: candidates are: int next [30][30][30][30][4]
 int n,m,data[50][50][5],dis[30][30][30][30],sx,sy,ex,ey,mx,my,next[30][30][30][30][4],ans;  
                                                               ^~~~
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/ostream:38,
                 from /usr/include/c++/6/iostream:39,
                 from /in/foo.cc:2:
/usr/include/c++/6/bits/stl_iterator_base_funcs.h:205:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
/in/foo.cc:159:6: error: reference to 'next' is ambiguous
   t1=next[x][y][xx][yy][0];
      ^~~~
/in/foo.cc:14:63: note: candidates are: int next [30][30][30][30][4]
 int n,m,data[50][50][5],dis[30][30][30][30],sx,sy,ex,ey,mx,my,next[30][30][30][30][4],ans;  
                                                               ^~~~
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/ostream:38,