C++ Calling a derived class function from the base class -


i'm not sure how call derived class function base class without getting sort of error, here's skeleton of code i'm trying work with...

class dicegame{ public:     virtual void play(){         // trying call derived class         // knockout's play function in here         // i've been trying          dicegame *game = new knockout;         game->play();          // gives me memory error     }  class knockout : public dicegame{     void play(){         // has stuff want call     }  main(){     dicegame *game = new dicegame();     game->play(); }

i have tried forward declaration of knockout class, gives me incomplete forward declaration error well, advice?

class dicegame{ public:     virtual void play() = 0; };  class knockout : public dicegame{ public:     virtual void play() { // replace "virtual" "override" here if compiler supports "override" keyword.         // has stuff want call     } };  int main() {     dicegame *game = new knockout();     game->play();     return 0; }

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