/in/foo.cc: In function 'void getnext()':
/in/foo.cc:25:8: error: reference to 'next' is ambiguous
    k = next[k-1];
        ^~~~
/in/foo.cc:11:5: note: candidates are: int next [201]
 int next[201];
     ^~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:66:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from /in/foo.cc:1:
/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
     ^~~~
/in/foo.cc:28:3: error: reference to 'next' is ambiguous
   next[i] = k;
   ^~~~
/in/foo.cc:11:5: note: candidates are: int next [201]
 int next[201];
     ^~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:66:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from /in/foo.cc:1:
/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
     ^~~~
/in/foo.cc: In function 'int kmp()':
/in/foo.cc:34:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i=0, j=0; i<T.length(); ++i) {
                     ~^~~~~~~~~~~
/in/foo.cc:36:8: error: reference to 'next' is ambiguous
    j = next[j-1];
        ^~~~
/in/foo.cc:11:5: note: candidates are: int next [201]
 int next[201];
     ^~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:66:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from /in/foo.cc:1:
/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
     ^~~~
/in/foo.cc:39:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if (j == P.length()) {
       ~~^~~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:48:9: error: reference to 'next' is ambiguous
  memset(next, 0, sizeof(next));
         ^~~~
/in/foo.cc:11:5: note: candidates are: int next [201]
 int next[201];
     ^~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:66:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from /in/foo.cc:1:
/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
     ^~~~
/in/foo.cc:48:25: error: reference to 'next' is ambiguous
  memset(next, 0, sizeof(next));
                         ^~~~
/in/foo.cc:11:5: note: candidates are: int next [201]
 int next[201];
     ^~~~
In file included from /usr/include/c++/7/bits/stl_algobase.h:66:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from /in/foo.cc:1:
/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
     ^~~~
/in/foo.cc: In function 'int kmp()':
/in/foo.cc:43:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^