下面的代码是多重继承的，每个类都有一个成员变量，一个普通函数和一个虚函数。classbasec{intx;public:basec(){x=0;}voidprint(){}virtualvoidxyz(){}};classderivedc:publicvirtualbasec{intdc;public:derivedc(){dc=0;}virtualvoidxyzdc(){}};classderivedd:publicvirtualbasec{intdd;public:derivedd(){dd=0;}virtualvoidxyzdd(){}};classchild:publicder