A.=和+ B.[]和后置-- C.前置--和[] D.=和[]
已知類A有一個(gè)帶double型參數(shù)的構(gòu)造函數(shù),且將運(yùn)算符“+”重載為友元函數(shù),要是語(yǔ)句序列 A x(2.5),y(3.6),z(0); Z=x+y; 能夠正常運(yùn)行,運(yùn)算符函數(shù)operator+應(yīng)在類中聲明為()。
A.friend A operator+(A,A); B.friend A operator+(int,A &,); C.friend A operator+(A,A &,); D.friend A operator+(A &,A &);
A.void B.char C.float D.int