foo.cc: In function 'void insect(int, int)':
foo.cc:11:26: error: reference to 'next' is ambiguous
 void insect(int x,int y){next[cnt]=point[x];point[x]=cnt;v[cnt]=y;cnt++;}
                          ^~~~
foo.cc:5:19: note: candidates are: int next [200003]
 int point[100003],next[200003],v[200003],cnt=0,N,l[100003],r[100003],pre[100003],con[100003];
                   ^~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:66:0,
                 from /usr/include/c++/7/algorithm:61,
                 from foo.cc:3:
/usr/include/c++/7/bits/stl_iterator_base_funcs.h:208:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
foo.cc: In function 'void dfs(int)':
foo.cc:16:29: error: reference to 'next' is ambiguous
     for (i=point[x];i!=-1;i=next[i])
                             ^~~~
foo.cc:5:19: note: candidates are: int next [200003]
 int point[100003],next[200003],v[200003],cnt=0,N,l[100003],r[100003],pre[100003],con[100003];
                   ^~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:66:0,
                 from /usr/include/c++/7/algorithm:61,
                 from foo.cc:3:
/usr/include/c++/7/bits/stl_iterator_base_funcs.h:208:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
foo.cc: In function 'void work(int)':
foo.cc:30:15: warning: unused variable 's' [-Wunused-variable]
     long long s=0; int num=1000000008;
               ^
foo.cc:30:24: warning: unused variable 'num' [-Wunused-variable]
     long long s=0; int num=1000000008;
                        ^~~
foo.cc: In function 'int main()':
foo.cc:105:12: error: reference to 'next' is ambiguous
     memset(next,-1,sizeof(next));
            ^~~~
foo.cc:5:19: note: candidates are: int next [200003]
 int point[100003],next[200003],v[200003],cnt=0,N,l[100003],r[100003],pre[100003],con[100003];
                   ^~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:66:0,
                 from /usr/include/c++/7/algorithm:61,
                 from foo.cc:3:
/usr/include/c++/7/bits/stl_iterator_base_funcs.h:208:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
foo.cc:105:27: error: reference to 'next' is ambiguous
     memset(next,-1,sizeof(next));
                           ^~~~
foo.cc:5:19: note: candidates are: int next [200003]
 int point[100003],next[200003],v[200003],cnt=0,N,l[100003],r[100003],pre[100003],con[100003];
                   ^~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:66:0,
                 from /usr/include/c++/7/algorithm:61,
                 from foo.cc:3:
/usr/include/c++/7/bits/stl_iterator_base_funcs.h:208:5: note:                 template<class _ForwardIterator> _ForwardIterator std::next(_ForwardIterator, typename std::iterator_traits<_Iter>::difference_type)
     next(_ForwardIterator __x, typename
     ^~~~
foo.cc:112:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d\n",&N);
     ~~~~~^~~~~~~~~~~
foo.cc:117:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d\n",&x,&y);
         ~~~~~^~~~~~~~~~~~~~~~~

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