This is ______ story-book. It was written by Yang Hongying.[ ]

A. the  

B. a  

C. an

有以下程序
void f( int y, int *x)
y=y+*x; *X=*X+y;
main()
int x=2,y=4;
f(y,&x);
printf("%d %d\n",x,y);

执行后输出结果是______。