main.cpp:27:7: error: redefinition of 'class Smth'
 class Smth : public Object {
       ^~~~
In file included from main.cpp:17:0:
factory.h:47:7: note: previous definition of 'class Smth'
 class Smth : public Object {
       ^~~~
main.cpp: In function 'int main()':
main.cpp:44:5: error: redefinition of 'int main()'
 int main() {
     ^~~~
In file included from main.cpp:17:0:
factory.h:86:5: note: 'int main()' previously defined here
 int main() {
     ^~~~