A.
int area( int length, int width ){ int s; s= length * width ; printf(“长方形面积是%d\n”, s);}
B.
int area( int length, int width ){ int s; s= length * width ; return s;}
C.
void area( int length, int width ){ int s; s= length * width ; printf(“长方形面积是%d\n”, s);}
D.
void area( int length, int width ){ int s; s= length * width ; return s;}