In file included from main.cpp:17:0:
figure.h: In function 'T CreateFigure(std::istringstream&)':
figure.h:71:28: error: expected initializer before '<' token
         Triangle shared_ptr<Triangle>(a, b, c);
                            ^
figure.h:76:22: error: expected initializer before '<' token
     Circle shared_ptr<Circle>(r);
                      ^
main.cpp: In function 'int main()':
main.cpp:33:37: error: no matching function for call to 'CreateFigure(std::istringstream&)'
    figures.push_back(CreateFigure(is));
                                     ^
In file included from main.cpp:17:0:
figure.h:57:3: note: candidate: template<class T> T CreateFigure(std::istringstream&)
 T CreateFigure(std::istringstream& is) {
   ^~~~~~~~~~~~
figure.h:57:3: note:   template argument deduction/substitution failed:
main.cpp:33:37: note:   couldn't deduce template parameter 'T'
    figures.push_back(CreateFigure(is));
                                     ^