有以下程序； void f(int *x,int *y) { int t; t=*x; *x=*y; *y=t; } main() { int a[8]={1,2,3,4,5,6,7,8},i,*p,*q; p=a; q=&a[7]; while (p＞q) { f(p,q);p++; q--; } for(i=0;i＜8; i++) printf( %d, ,a[i]); } 程序运行后的输出结果是( )。
A．8,2,3,4,5,6,7,1,
B．5,6,7,8,1,2,3,4,
C．1,2,3,4,5,6,7,8,
D．8,7,6,5,4,3,2,1,