class - C++: Deriving with variables. Something is wrong with a small section of code -

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classes dog , cat derive animal, in turn derives creature. pdog, pcat, panimal, , pcreature pointers class. animal , creature both abstract classes.

what wrong code?

panimal = new dog(); pdog = panimal;

you can convert up hierarchy (i.e., derived base) implicitly.

converting down hierarchy (from base derived) has done explicitly. in cases, want use dynamic_cast conversion succeed if correct:

animal *panimal = new dog();  dog *pdog = dynamic_cast<dog *>(panimal);

note classes need contain @ least 1 virtual function work (but if don't have virtual functions, hierarchy doesn't make sense @ all).


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