/in/foo.cc: In constructor 'reader::reader()':
/in/foo.cc:30:11: error: no matching function for call to 'xiang::xiang()'
   reader(){
           ^
/in/foo.cc:18:3: note: candidate: xiang::xiang(int, int)
   xiang(int xishu, int zhishu){
   ^~~~~
/in/foo.cc:18:3: note:   candidate expects 2 arguments, 0 provided
/in/foo.cc:15:8: note: candidate: constexpr xiang::xiang(const xiang&)
 struct xiang {
        ^~~~~
/in/foo.cc:15:8: note:   candidate expects 1 argument, 0 provided
/in/foo.cc:15:8: note: candidate: constexpr xiang::xiang(xiang&&)
/in/foo.cc:15:8: note:   candidate expects 1 argument, 0 provided
/in/foo.cc: In member function 'void reader::init()':
/in/foo.cc:39:23: error: no match for 'operator=' (operand types are 'xiang' and 'xiang*')
     x = new xiang(0, 0);
                       ^
/in/foo.cc:15:8: note: candidate: xiang& xiang::operator=(const xiang&)
 struct xiang {
        ^~~~~
/in/foo.cc:15:8: note:   no known conversion for argument 1 from 'xiang*' to 'const xiang&'
/in/foo.cc:15:8: note: candidate: xiang& xiang::operator=(xiang&&)
/in/foo.cc:15:8: note:   no known conversion for argument 1 from 'xiang*' to 'xiang&&'
/in/foo.cc: In member function 'xiang reader::read(char)':
/in/foo.cc:82:38: error: no match for 'operator-' (operand types are 'xiang' and 'char')
         x.zhishu = x.zhishu * 10 + (x-'0');
                                     ~^~~~
In file included from /usr/include/c++/6/bits/stl_algobase.h:67:0,
                 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:1:
/usr/include/c++/6/bits/stl_iterator.h:333:5: note: candidate: template<class _Iterator> decltype ((__x.base() - __y.base())) std::operator-(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_Iterator>&)
     operator-(const reverse_iterator<_Iterator>& __x,
     ^~~~~~~~
/usr/include/c++/6/bits/stl_iterator.h:333:5: note:   template argument deduction/substitution failed:
/in/foo.cc:82:39: note:   'xiang' is not derived from 'const std::reverse_iterator<_Iterator>'
         x.zhishu = x.zhishu * 10 + (x-'0');
                                       ^~~
In file included from /usr/include/c++/6/bits/stl_algobase.h:67:0,
                 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:1:
/usr/include/c++/6/bits/stl_iterator.h:387:5: note: candidate: template<class _IteratorL, class _IteratorR> decltype ((__y.base() - __x.base())) std::operator-(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_IteratorR>&)
     operator-(const reverse_iterator<_IteratorL>& __x,
     ^~~~~~~~
/usr/include/c++/6/bits/stl_iterator.h:387:5: note:   template argument deduction/substitution failed:
/in/foo.cc:82:39: note:   'xiang' is not derived from 'const std::reverse_iterator<_Iterator>'
         x.zhishu = x.zhishu * 10 + (x-'0');
                                       ^~~
In file included from /usr/include/c++/6/bits/stl_algobase.h:67:0,
                 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:1:
/usr/include/c++/6/bits/stl_iterator.h:1186:5: note: candidate: template<class _IteratorL, class _IteratorR> decltype ((__x.base() - __y.base())) std::operator-(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorR>&)
     operator-(const move_iterator<_IteratorL>& __x,
     ^~~~~~~~
/usr/include/c++/6/bits/stl_iterator.h:1186:5: note:   template argument deduction/substitution failed:
/in/foo.cc:82:39: note:   'xiang' is not derived from 'const std::move_iterator<_IteratorL>'
         x.zhishu = x.zhishu * 10 + (x-'0');
                                       ^~~
In file included from /usr/include/c++/6/bits/stl_algobase.h:67:0,
                 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:1:
/usr/include/c++/6/bits/stl_iterator.h:1193:5: note: candidate: template<class _Iterator> decltype ((__x.base() - __y.base())) std::operator-(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorL>&)
     operator-(const move_iterator<_Iterator>& __x,
     ^~~~~~~~
/usr/include/c++/6/bits/stl_iterator.h:1193:5: note:   template argument deduction/substitution failed:
/in/foo.cc:82:39: note:   'xiang' is not derived from 'const std::move_iterator<_IteratorL>'
         x.zhishu = x.zhishu * 10 + (x-'0');
                                       ^~~