单项选择题
A.x.Operator/(y) B.operator/(x,y) C.y.operator/(x) D.operator/(y,x)
A.int function(int m,int n); B.int function(int,int); C.int function(int m=3,int n); D.int function(int &m,int &n);
A.2 B.5 C.4 D.9