View Compilation Error

0_0_36592835_11020.cpp: In function 'int main()':
0_0_36592835_11020.cpp:37:43: error: cannot bind 'std::ostream {aka std::basic_ostream<char>}' lvalue to 'std::basic_ostream<char>&&'
                     cout << doctor[a].top() <<endl;
                                           ^
In file included from GCC4.9.2/x86_64-w64-mingw32/include/c++/istream:39:0,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/sstream:38,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/complex:45,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/ccomplex:38,
                 from GCC4.9.2/x86_64-w64-mingw32/include/c++/x86_64-w64-mingw32/bits/stdc++.h:52,
                 from 0_0_36592835_11020.cpp:1:
GCC4.9.2/x86_64-w64-mingw32/include/c++/ostream:602:5: note: initializing argument 1 of 'std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&&, const _Tp&) [with _CharT = char; _Traits = std::char_traits<char>; _Tp = patient]'
     operator<<(basic_ostream<_CharT, _Traits>&& __os, const _Tp& __x)
     ^