Error(s):

C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\deque(947) : error C2027: use of undefined type 'some'
        source_file.cpp(7) : see declaration of 'some'
        C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\stack(21) : see reference to class template instantiation 'std::deque<_Ty,std::allocator<_Ty>>' being compiled
        with
        [
            _Ty=some
        ]
        source_file.cpp(11) : see reference to class template instantiation 'std::stack<some,std::deque<_Ty,std::allocator<_Ty>>>' being compiled
        with
        [
            _Ty=some
        ]
        source_file.cpp(7) : see declaration of 'some'
        source_file.cpp(7) : see declaration of 'some'
        source_file.cpp(7) : see declaration of 'some'
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\deque(948) : error C2027: use of undefined type 'some'
        source_file.cpp(7) : see declaration of 'some'
        source_file.cpp(7) : see declaration of 'some'
        source_file.cpp(7) : see declaration of 'some'
        source_file.cpp(7) : see declaration of 'some'
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\deque(947) : error C2027: use of undefined type 'example2'
        source_file.cpp(15) : see declaration of 'example2'
        C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\stack(21) : see reference to class template instantiation 'std::deque<_Ty,std::allocator<_Ty>>' being compiled
        with
        [
            _Ty=example2
        ]
        source_file.cpp(16) : see reference to class template instantiation 'std::stack<example2,std::deque<_Ty,std::allocator<_Ty>>>' being compiled
        with
        [
            _Ty=example2
        ]
        source_file.cpp(15) : see declaration of 'example2'
        source_file.cpp(15) : see declaration of 'example2'
        source_file.cpp(15) : see declaration of 'example2'
C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\INCLUDE\deque(948) : error C2027: use of undefined type 'example2'
        source_file.cpp(15) : see declaration of 'example2'
        source_file.cpp(15) : see declaration of 'example2'
        source_file.cpp(15) : see declaration of 'example2'
        source_file.cpp(15) : see declaration of 'example2'