算法partition中元素交换条件改为i<=p,元素如下:15,14,13,12,15,19,16,18,17,经过一次划分后列表是 ( )
A. 15,14,13,12,15,19,16,18,17
B. 12,14,13,15,15,19,16,18,17
C. 2,3,4,5,5,6,7,8,9
A. 15,14,13,12,15,19,16,18,17
B. 12,14,13,15,15,19,16,18,17
C. 2,3,4,5,5,6,7,8,9