That's the finger thing from left finger to right finger going back and forth across the board, never touching a number more than once.

在合并时，我的左手手指,和右手手指来回地在黑板上移动，但对每个数字只会碰到一次。

哈佛公开课 - 计算机科学课程节选

N But it's definitely not one and in fact it wasn't N in the case of Selection Sort because remember the algorithm we implemented on stage last week had me going back and forth across the stage selecting on iteration, the smallest person I can find, the smallest number and then putting them into place.

但在选择排序中，肯定不会是1，也不是,注意，上周我们在这儿,实现的算法中，反复地,迭代进行选择，选出最小的数,然后将其放在合适的位置。

哈佛公开课 - 计算机科学课程节选