void MainMenu::OnSinglePlayer() {
SinglePlayerMenu* mySinglePlayer = new SinglePlayerMenu();
if(mySinglePlayer == NULL) {
perror("MainMenu::OnSinglePlayer()");
exit(EXIT_FAILURE);
}
mySinglePlayer->showMenu();
delete mySinglePlayer;
}
void MainMenu::onSinglePlayer() {
SinglePlayerMenu* pSinglePlayerMenu = new SinglePlayerMenu();
pSinglePlayerMenu->showMenu();
delete pSinglePlayerMenu;
}