3、以下正确的函数定义是( ).A.double fun(int x,int y); {int z; z=x+y; return z;}

3、以下正确的函数定义是( ).

A.double
fun(int x,int y);

{int z;

z=x+y; return z;}

B.fun(int x,y)

{int z; return z;}

C.double
fun(int x,int y);

{double z;

z=x+y;
return z;}

D.double fun(
x, y)

int x,y;

{double z; z=x+y; return z;}
C对的。AB返回值和函数定义不一致,D的int x,y定义不能在fun()和{}中间